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The article considers the issues of assuring the quality of the surfaces of machine parts by applying a preliminary local thermal impact before their edge cutting machining. In the zone of application of local thermal impact, a zone of metastable structure with respect to the material of the workpiece to be treated occurs. When the cutting plane intersects with the local thermal application line, the formed flow chip is segmented. The created graphs allow assigning of local thermal modes to the surface of the workpiece before edge cutting machining. Application of preliminary local thermal impact will assure the specified quality of the surface of the treated workpiece at semi-finishing and finishing edge cutting machining modes and stable segmentation of the flow chip.

The focus of this work is the analysis of the thermal impact and its depth effect in different grinding processes. The investigated processes cover different kinematics and thus broad ranges of the relative speeds and the intensities of the moving heat source regarding the ground surface. A uniform lower process limit characterizing the onset of grinding burn for the different kinematics is identified by means of the specific grinding power and the contact time. The experimental results together with the theoretical considerations of peak temperatures lead to the conclusion that the process specific range of the contact time is mainly responsible for the thermal depth effect. The results enable the targeted exceeding of the critical process limit in roughing and the subsequent correction by finishing.

20th CIRP Conference on Electro Physical and Chemical Machining, ISEM 2020, online, 19 Jan 2021 - 21 Jan 2021; Procedia CIRP 95, 238-243 (2021). doi:10.1016/j.procir.2020.01.149 special issue: "20th CIRP Conference on Electro Physical and Chemical Machining / Edited by Konrad Wegener, Moritz Wiessner", Published by Elsevier, Amsterdam [u.a.]

Objectives This work was devoted to the research of thermal processes that occur in the reflex areas of the human body, in particular, in reflexogenic areas of the human foot, under the thermal influence under ambulatory conditions.Method A model of thermal impact on the reflex areas of the human body was developed on the basis of a semiconductor thermoelectric device. A simplified physical model was studied, which does not consider heat exchange in thermoelectric batteries (TEBs) and elements of TEBs pairing with separate reflex zones.Results Diagrams for temperature distribution throughout the foot at different values of heat flow and diagrams of temperature changes over time were obtained. The thermal influence of a TEB brought in thermal contact with the opposite surface of the foot is negligible in this case; this is due to the low thermal conductivity of foot tissues, as well as insignificant thermal flows on its surface (low-power TEBs were used for such procedures).Conclusion The developed model of a semiconductor thermoelectric device for treating the reflex areas of the human body – in particular, the foot – allows an investigation of thermal processes occurring during the thermal treatment of biologically active points of the human sole. It is established that local temperature impact on a biological object does not result in significant temperature difference over its thickness.

Experiments on subcooled flow boiling have been carried out to investigate the dynamical parameters and thermal impact of a growing vapor bubble under vertically upward and downward flow configurat...

Although CO2 storage has been comprehensively investigated, fewer scholars have taken the effect of temperature and the dual-porosity structure of coal into account, which brought a large d...

The use of shallow geothermal energy increasingly receives attention as a suitable alternative to fossil fuel-based space heating and cooling, warm water provision, as well as for seasonal heat storage throughout Europe. With the advent of shallow geothermal energy use on large scales, a vivid discussion of potential ecological and economic impacts has arisen but actual field data are scarce. An intensive groundwater temperature-monitoring program over a period of 3 years with consecutive measurements was, therefore, initiated at a residential neighborhood in the city of Cologne, Germany, under intense shallow geothermal use. The aim of the monitoring program was to overcome the existing data scarcity by pinpointing the effects of the intensive thermal use of the subsurface on groundwater temperatures and to foster understanding of urban groundwater temperature evolution. Results show that even though energy demands of the individual houses and energy extraction rates of the shallow geothermal systems were comparably small in this case, the accumulation of shallow geothermal users had a measurable impact on overall groundwater temperatures.

The aim of this study is to demonstrate the requirement to integrate the urban microclimate to predict the energy needs of buildings. To do this, an integrated approach in TRNSYS software was developed and compared with existing experimental results of a street canyon. Afterwards, a case study was carried out in the case of a street canyon located in the city of Tangier in Morocco. The impact of the aspect ratio on the temperature of the building surfaces and the radiation absorbed by them was examined. The results show that there is greater radiation absorption on the building facades in street canyons than on those of stand-alone buildings. These effects lead to higher surface temperatures in street canyons, resulting in increased cooling energy needs in summer and reduced heating energy needs in winter.

Lithium-ion batteries, with high energy density (up to 705 Wh/L) and power density (up to 10,000 W/L), exhibit high capacity and great working performance. As rechargeable batteries, lithium-ion batteries serve as power sources in various application systems. Temperature, as a critical factor, significantly impacts on the performance of lithium-ion batteries and also limits the application of lithium-ion batteries. Moreover, different temperature conditions result in different adverse effects. Accurate measurement of temperature inside lithium-ion batteries and understanding the temperature effects are important for the proper battery management. In this review, we discuss the effects of temperature to lithium-ion batteries at both low and high temperature ranges. The current approaches in monitoring the internal temperature of lithium-ion batteries via both contact and contactless processes are also discussed in the review. Keywords: Lithium-ion battery, Temperature effect, Internal temperature, Battery management, Thermal management

Voltage unbalance and mechanical overload generate negative effects on induction motors, producing thermal damages in the stator insulation and a reduction of the motor lifetime. In this regard, the development of protection devices is crucial as they can help to maintain the integrity of the motor and avoid irreversible damages such as insulation system breakdown, short-circuits, and so on. In this work, a methodology to obtain a time-protection model for induction motors from voltage unbalance is presented. The methodology is based on the thermal impact on the motor produced by mechanical overload and voltage unbalance conditions. In general, it consists of the following steps: i) induce in the motor different overloads and voltage unbalance levels and monitor their thermal profiles at the stator winding, ii) obtain the time–overload curve of the motor, iii) determine both the thermal level according to both the time-overload curve and the overload thermal profile, and iv) estimate the parameters of the time-unbalance model using both the thermal level obtained and the unbalance thermal profiles. The model is validated through its implementation in an online protection scheme, the results show a similar behavior between overload and unbalance protections in the safe thermal level defined by the protection models. The protection scheme is carried out over a 750 W three-phase induction motor under different overload and voltage unbalance operating conditions.

Adhesive mounting of residential rooftop photovoltaics (PV) is an alternative to traditional rack mounting that reduces installation costs. Adhesive mounting is fast, simple and reduces the need for skilled labor. In our novel design that further reduces the installation costs, a lightweight (glassless and frameless) PV module is directly adhered to a shingled roof using an adhesive tape, creating a

De nombreuses études ont été effectuées sur l’impact thermique des plans d’eau sur les cours d’eau. Sur les têtes de bassin hydrographiques, l’attention est généralement portée aux cours d’eau, laissant de côté la dynamique interne au plan d’eau. Or, pour les étangs, classés polymictiques discontinus, où les brassages alternent à l’échelle de quelques jours avec les phases de stratification thermique, la connaissance de la dynamique du plan d’eau est fondamentale dans la compréhension de l’évolution amont-aval de la température au sein d’un bassin versant. La présente étude adopte une approche limnosystémique afin de comprendre la dynamique annuelle des étangs en tête de bassin. Pour l’étang multilobé de la Ramade (Puy de Dôme), les écarts de chaleur entre la surface et le fond dépassent les 13 °C pendant certaines périodes, tandis qu’ils peuvent atteindre les 7 °C de différence spatiale entre ses bassins. L’approche spatiale de la température de l’eau permet de faire ressortir de nouveaux indicateurs, tel que le centre thermique. L’étude de son évolution est un moyen efficace à la compréhension globale de la répartition de chaleur au sein du plan d’eau, dans l’espace et dans le temps. Par la forte disparité spatiale de température des étangs, représentée dans le centre thermique, des intérêts de gestion forts émanent de ces problématiques. La modification possible de la position de la sortie d’eau ainsi que des aménagements pourraient permettre de limiter l’influence thermique de l’étang, au centre du système lotique. L’étude d’un grand étang influencé par des courses du vent longues et un très petit étang influencé par un effet d’abris topographique et végétal montrent différentes possibilités de variation spatiale de la température. Many studies have focused on the thermal impact of waterbodies on downstream waterways. With respect to headwaters, interest has tended to focus on streams, neglecting the internal dynamics of waterbodies. For ponds, defined as discontinuous polymictic waterbodies with a maximum depth of less than 6 m (19.7 ft) and an area of less than 100 ha (250 acres), the mixing and stratification stages frequently alternate. Therefore, knowledge of a waterbody’s dynamics is key to understanding the upstream–downstream temperature trends within a drainage basin. This study is based on a limnosystemic approach in order to study the annual thermal dynamics of two ponds located on headwaters. The first, Étang de La Ramade (La Ramade Pond), in the French département of Puy-de-Dôme in Auvergne, is a pond of 62 ha (153 acres), with a mean depth of 1,1 m (3.6 ft) and a maximum depth of 3,5 m (11.5 ft) (figure 1). Its morphology lends itself to significant spatial variations in temperature. The second pond is the Étang de Rilhac (Rilhac Pond), located close to Limoges in the French Department of Haute-Vienne (Limousin). This is a 0.4‑ha (1‑acre) pond, with a maximum depth of 4,2 m (13.8 ft) and a mean depth of 2 m (6.6 ft). Rilhac Pond is representative of small headwater ponds, damming a small valley. In order to measure the temperature within the pond, the methodology implemented uses a number of chains hung on a flotation device, with data loggers to measure the temperature every hour and every 25 cm (10 in.) from the surface to the bottom, at six different locations. The heat-content approach, which multiplies the temperature recorded by the volume of each layer of a column of water, takes account of all factors – internal and external – that influence the waterbody temperature. The temperature can vary vertically by up to 13 °C (23 °F) between the surface and the bottom, with differences of up to 7 °C (13 °F) between one measuring location and another. Adopting a geographical approach to water temperature makes it possible to highlight certain new indicators such as the heat center. Studying changes in the heat center is useful in gaining an overall comprehension of the spatial and temporal temperature trends within the waterbody. Heat-center variations can be significant, and depend on a number of factors, such as the stratification and mixing of the water column and the temperature distribution within the waterbody. Latitudinal, longitudinal and depth variations in the heat center can be analyzed either separately – so as to obtain specific data for each – or all together, for a comprehensive overview. The variations in the dynamics of a pond’s different sub-basins in comparison with the central part of the pond can be expressed through the heat center. This new indicator may have a number of benefits in the field of pond management – allowing, for example, outflow locations to be modified or correctly selected, and surrounding areas to be easily be adapted in order to reduce a pond’s effect on a stream system.

UHI is the most studied phenomenon of climate change and refers to the increased ambient temperature of cities compared to rural settings. Implementation of reflective materials to urban structures, such as roads and pavements, reduces the surface and ambient temperature and contributes to counterbalance the impact of the phenomenon. The present paper describes the design and the experimental evaluation of a large scale implementation of cool asphaltic and concrete pavements in a major traffic axis of Western Athens covering a total zone of 37,000 m2. To our knowledge, this project is one of the largest urban mitigation projects in the world. Extended monitoring was performed in the area during the entirety of the summer period, while Computational Fluid Dynamics (CFD) simulation was used to evaluate the thermal impact of the application. It was concluded that the use of cool non-aged asphalt can reduce the ambient temperature by up to 1.5 °C and the maximum surface temperature reduction could reach 11.5 °C, while the thermal comfort conditions can improve considerably. Ageing phenomena may reduce substantially and up to 50% the mitigation potential of cool asphaltic materials.

Although multi-branch horizontal well coalbed methane (CMB) extraction has been comprehensively investigated, fewer scholars have taken the effect of temperature into account, which brought a large...

In the past decades, increasing attention has been directed to understanding the structural response to various scenario fires, which is stimulated by the trend of considering localised burning in large open plan compartments. Beam-column elements as widely used in modelling steel frames have been extended to account for the thermal impact in OpenSees, the development of which is undertaken to formulate the displacement and force-based beam elements. After including the non-uniform thermal expansion along the element length caused by localised heating, the force-based beam-column element has shown greater efficiency compared to the displacement-based element. A detailed discussion regarding the computational performance of both beam-column elements has been presented in this paper, which concludes that force-based beam-column elements can better represent the localised plasticity of fibres caused by non-uniform heating. A generic simply supported steel beam can be modelled even with two force-based elements to reproduce accurate mid-span deflection under localised heating. A steel beam subjected to a localised fire is presented as a case study in this paper, experiencing run-away collapse after 15 min of exposure when the load ratio reaches 50%. Using a 12 element force-based beam-column model and shows equivalent accuracy against 48 element displacement-based beam-column model.

The thermal impact of the birds’ color on their flight performance are investigated. In most of the large migrating birds, the top of their wings is black. Considering this natural phenomenon in the migrating birds, such as albatross, a thermal analysis of the boundary layer of their wings is performed during the year depending on the solar insulation. It is shown that the temperature difference between the bright and dark colored top wing surface is around 10 °C. The dark color on the top of the wing increases the temperature of the boundary layer over the wing which consequently reduces the skin drag force over the wing. This reduction in the drag force can be considered as one of the effective factors for long endurance of these migrating birds. This research should lead to improved designs of the drones by applying the inspired colors which can help drones increase their endurance.

In this paper, the transient experimental validation of the convolution-based fast thermal model (FTM) for 3-D integrated circuits is presented. The methodology is proven to be applicable to analyze the temperature evolution of real devices. A low-power package configuration with two different power dissipation scenarios, hotspot (HS) in the corner and HS in the center of the active region, has been considered for the validation. In this way, the importance of the package thermal impact on the definition of the final temperature profiles is highlighted. The error between the measurement and the FTM results remains always below 2.3 °C/W. Moreover, the model has been validated with respect to case studies concerning duty cycles of different durations. This proves the applicability of the model in defining the allowed duration of the chip activity before a maximum threshold temperature is reached. Finally, in this paper, the possibility to use a variable time-step approach in the transient FTM is presented together with the option of computing the temperature in individual points only. This is possible maintaining the same accuracy as if the fully resolved temperature maps would be calculated.

An industry consortium study, Energy Resistance of Commercial Roofs (ERCR), has been developed by NRC to develop scientifically supported performance data on energy resistance of roofing systems that are constructed according to field practices. The ERCR consortium project had two major tasks. In Task 1, the objective was to evaluate the effective thermal resistance of current roof designs and validate their compliance with the energy code requirements and, in Task 2, the aim was to quantify the two thermal impact factors – thermal bridging from fasteners and thermal bypass from gaps between the insulation boards. This paper focuses on the Task 2-thermal bridging from fasteners. More than 100 experiments were conducted to quantify the impact of fastener density, fastener location, fastener diameter, and fastener penetration depth on the thermal performance of the roofing assembly. From the experimental data, the thermal bridging of fasteners was quantified in terms of the “Relative” decrease in effective R-value and Chi-factors (χ). The impact of fastener density revealed that the thermal bridging increases with the fastener density and also with the thermal resistance of the insulation with an average loss in effective R-value ranging from 5% to 14% for the tested configurations. The increase in the fastener diameter or the fastener area (#12 < #14 < #15) increases the overall heat flow through the assembly. In a multilayer insulation layout, fasteners installed in the bottom layer are shielded by the top insulation and can reduce thermal bridging from 30% to 70% relative to the through fastener from the top layer. From the experimental data, chi factors were developed to support calculation of point thermal bridging effects on the thermal performance of the commercial roofs, and also to fill in the missing gaps in the energy codes towards the thermal design of roofs.

Electrical discharge machining (EDM) is a non-conventional machining technique for removing material based on the thermal impact of a series of repetitive sparks occurring between the tool and workpiece in the presence of dielectric fluid. Since the machining characteristics are highly dependent on the dielectric’s performance, significant attention has been directed to modifying the hydrocarbon oil properties or introducing alternative dielectrics to achieve higher productivity. This article provides a review of dielectric modifications through adding powder to dielectric. Utilizing powder mixed dielectric in the process is called powder mixed EDM (PMEDM). In order to select an appropriate host dielectric for enhancing machining characteristics by adding powder, a brief background is initially provided on the performance of pure dielectrics and their selection criteria for PMEDM application follow by powder mixed dielectric thoroughly review. Research shows that PMEDM facilitates producing parts with predominantly high surface quality. Additionally, some studies indicate that appropriate powder selection increases machining efficiency in terms of material removal rate. Therefore, the role of powder addition in the discharge characteristics and its influence on machining output parameters are explained in detail. Furthermore, by considering the influence of the main thermo-physical properties and concentration of powder particles, the performance of various powder materials is discussed extensively. Since suitable powder selection depends on many factors, such as variations in EDM, machining scale and electrical and non-electrical parameter settings, a thorough comparative review of powder materials is presented to facilitate a deeper insight into powder selection parameters for future studies. Finally, PMEDM research trends, findings, gaps and industrialization difficulties are discussed extensively.

The temperature of hot forging dies has a high influence on the wear of tool surfaces. In order to reduce the thermal impact on tool life, passively acting heat pipes are tested and the results are presented within this paper. For this purpose, the upper die of a commonly used hot forging tool was equipped with heat pipes and serial forging trials have been performed. The influence of the heat pipes on the die temperature as well as the effects on wear behavior are presented. The heat pipe cooling leads to a lower die temperature and thus to a reduction of adhesive wear. The wear is examined by optical and tactile measurements as well as by micrograph analyses. Conclusively, hardness tests of the tool edge layer are carried out.

In this study, the conjoint effect of a broaching operation, similar to that used for machining fir-tree slots on turbine discs, and subsequent heat treatments at 550 °C and 650 °C on the fatigue p ...

Investigating the thermal impact including the fluctuations of the solar irradiance and ambient temperature of photovoltaic (PV) systems is a topic of great interest by industry and policymakers, due to the limited case studies reported so far by the PV research community. Therefore, this article presents the analysis of 8000 PV systems distributed across England using the well-known metric, monthly performance ratio (PR). The PV systems were operated over five years, while the PR is calculated using the newly developed model by the US national renewable energy laboratory (NREL). Remarkably, it was found that the average monthly PR for all examined PV systems is equal to 85.74%, where the Midlands region in the UK has the highest monthly PR of 88.12%. We have also investigated the seasonal thermal impact on the performance of PV systems, where it was concluded that Spring and Summer seasons intend to have higher monthly PR compared to Autumn and Winter. Finally, a detailed experiment of three different PV modules affected by various hotspots, including cell-based and string-based, will be comprehensively discussed.

This paper presents a study on the crack behavior under a thermal shock in a wide range of applications. The Stress Intensity Factors (SIFs) for a stationary crack under a non-Fourier thermal shock according to the Green-Naghdi (GN) theory is computed. The crack is considered as an adiabatic line in the framework of the eXtended Finite Element Method. The interaction integral is employed to extract the SIFs for three types of the Green-Naghdi theory. The differences in the time history of SIFs due to the thermal shock based on all types of the GN theory is studied. Also, the effect of damping coefficient on the SIFs and the temperature field is investigated. Finally, the role of inclined cracks, which disturb the time history of SIFs, displacement and temperature distributions for type II and III of the GN theory are discussed.

The paper describes the study of the ignition of wood samples treated with a flame retardant in the presence of different ignition sources (firebrands, pine needle litter) under the laboratory conditions, and to obtain data on fire resistance of wood samples exposed to heat. The charring depth of the wood samples was determined depending on the type of wood, as well as on the type of the fire retardant used. The experimental results show that fire retardants significantly increase the protective properties of wood exposed to firebrands.

The transfer of heat in an underground environment is due to circumstances, natural and introduced elements. In an underground mine, the heat is generated by the geothermal gradient, the self-compression of the rocks, the use of explosives, diesel equipment and human metabolism, etc. Since any or all of them can be heat generators, it is important to control the temperature and humidity in the mines, both to understand the nature of the heat sources and to calculate or estimate the magnitude of the flow of this. (Hartman et al, 1997) [4]. The increase of the temperature in underground environments generates risks, which can cause tragedies in the worst cases. Two main aspects must be taken into account due to the risk generated by high temperatures: one is the affectation to the corporal health of the workers and the other is the impact on the safety and productivity of the mine. (Su et al, 2009) [9]. When humidity and temperatures are high in an underground environment, workers suffer from a feeling of not comfort, generating stress in them, and this in turn leads to an increase in accidents and a decrease in productivity. As the depth increases and the level of mechanization increases, the high temperatures and the damages produced by the heating, are the biggest problems that the mining safety presents, limiting the activity in the coal mines. (Song and Xie, 2011) [8] (Xie, Z., 2012) [11] As a referent, in Table I, the percentage of accidents due to an increase in air temperature is related to gold mines in South Africa. (C. Anguo.2004) [1].

Most of the magnificent wall paintings from the ancient city of Pompeii are decorated with red and yellow colors coming from the ochre pigments used. The thermal impact of the pyroclastic flow from the eruption of Vesuvius, in AD 79, promoted the transformation of some yellow painted areas to red. In this work, original red ochre, original yellow ochre, and transformed yellow ochre (nowadays showing a red color) of wall paintings from Pompeian houses (House of Marcus Lucretius and House of Gilded Cupids) were analyzed by means of a handheld energy-dispersive X-ray fluorescence spectrometer to develop a fast method that allows chemical differentiation of the original red ochre and the transformed yellow ochre. Principal component analysis of the multivariate obtained data showed that arsenic is the tracer element to distinguish between both red colored ochres. Moreover, Pompeian raw red and yellow ochre pigments recovered from the burial were analyzed in the laboratory with use of a benchtop energy-dispersive X-ray fluorescence spectrometer to confirm the elemental composition and the conclusions drawn from the in situ analysis according to the yellow ochre pigment transformation in real Pompeian wall paintings.

Femtosecond laser-germanium interaction was simulated to predict the thermal impact of laser processing parameters. Initial experimental processing was carried out to investigate predicted thermal impact on germanium material removal and surface quality.

Contamination adhered to the surface of a µCMM stylus tip compromises the measurement accuracy of the µCMM system, potentially causing dimensional errors that are over ten times larger than the uncertainty of a modern µCMM. In prior work by the authors, the use of a high pressure CO2 gas stream was demonstrated to achieve significant cleaning rate for a range of contaminant without damage to the stylus tip surface. This paper explores the practical challenges of achieving effective stylus tip cleaning in situ on µCMM systems. Two types of snow cleaning approaches were evaluated for their coverage of cleaning, thermal impact and gas flow forces. This work then presents a novel multi-nozzle prototype system using pulsed snow streams to achieve cleaning coverage over the entire stylus tip, and balances forces from the snow streams reducing drag force imparted by the gas stream to levels comparable to the probing force of µCMMs, as well as allowing automated cleaning procedure integrated into a µCMM system.

This paper presents a study on the thermal impact of the back-end-of-line (BEOL) in a state-of-the-art SiGe HBT technology for high power applications. A recursive RC network is proposed to model the thermal behavior of the BEOL and is validated with measurements on dedicated test-structures in the time and frequency domain.

Clays and claystones are considered in some countries (including Belgium, France and Switzerland) as a potential host rock for high activity long lived radioactive waste disposal at great depth. One of the aspects to deal with when assessing the performance of the disposal is related to the effects of the temperature elevation due to the placement of exothermic wastes on the host rock. The potential effects of the thermal impact on the excavation damaged zone (EDZ) in the near field are another important issue that was the goal of the TIMODAZ European research project. In this paper, some principles of waste disposal in clayey host rocks at great depth are first presented and a series of experimental investigations carried out on specific equipment specially developed to face the problem are presented. Both drained and undrained tests have been carried out to investigate the drained thermal volume changes of clays and claystone and the thermal pressurization occurring around the galleries. The importance of proper initial saturation (under in situ stresses) and of satisfactory drainage conditions (in spite of the significantly low permeability of claystones) is emphasized, leading to the development of a new hollow cylinder apparatus. It is observed that claystones cannot be considered as overconsolidated clays given that they can exhibit, as the Callovo-Oxfordian claystone does, a thermoplastic contraction. Mechanical and thermal hardenings are however observed, extending the knowledge already gained on clays to claystones. A new method of determining the thermal pressurization coefficient in the laboratory is described and the data obtained allow completing existing data in the field. Finally, the hollow cylinder apparatus makes it possible to demonstrate that the good self-sealing properties of clays and claystones can be extended to temperature effects, an important conclusion in terms of performance assessment.

The body of an 89-year-old woman was discovered at home by a member of her family. Only part of the body, the legs, were found intact without burn damage. The rest of the body was burned to ashes without the possibility to identify the cadaver. Forensic Dentistry had two main goals to resolve in this forensic pathology casework, and they were: 1) establish the identification of the cadaver; and 2) estimate the temperature and the direction of the fire by the analysis and interpretation of the skeletal intraoral dental materials altered by thermal processes. This case study manuscript focuses only on the second objective. The effects of fire on teeth are influenced by the temperature applied and by its duration. Additionally, adjacent tissues as well as temperature alterations caused by substances used to quench the fire have been shown to affect the thermal impact on teeth and their restoration. Bodies may be subjected to various temperatures, depending on the origin of the fire and the conditions that promote continuation of the blaze. Fire effects on certain dental materials can indicate the direction and the temperature of a fire. This is based on the physical, mechanical, and chemical changes of different dental materials resulting from high temperatures. The distinct properties of various dental materials, well defined, can influence and predict their performance under different degrees of fire. In this case study, the cadaver had two main groups of dental materials: metal alloys and polymers. The importance of the detailed degree of predictability of fire performance data from thermal decomposition data should not be underestimated; polymers cannot burn if they do not break down and metal alloys cannot burn if the melting point is not reached, independent of the variable time of the fire.

The geometrical and physical properties of the surface and the near-surface layers can be modified by a mechanical or a thermal impact. If these variations are coupled with a modification of the thermal properties, they become detectable by photothermal means. In order to perform some fundamental experiments, we chose the Vickers hardness test as a model for a slight and reproducible mechanical impact. The surroundings near the deformed areas were scanned ; the optical beam deflection as well as the radiometric signal were measured and compared with the optical microscopic images.