Search

This document provides an overview of the failure analysis process for castings used in mineral ore processing. It emphasizes the significance of visual examination, material testing, and metallographic examination in determining the cause of failure. The document includes two case studies that illustrate the complexities of failure analysis in these materials. The findings from these case studies underscore the importance of proper installation procedures and mill operation to prevent future failures. Thorough documentation and reporting throughout the failure analysis process are also emphasized. [Extracted from the article]

In the present study, a face-centered cubic non-equiatomic Cr 26 Mn 20 Fe 20 Co 20 Ni 14 high-entropy alloy (HEA) with a low stacking fault energy of 17.6 mJ m−2 was prepared by vacuum induction melting, forging and annealing processes. The recrystallized sample is revealed to exhibit an excellent combination of strength and ductility over a wide temperature range of 4.2–293 K. With decreasing temperature from 293 to 77 K, the ductility and ultimate tensile strength (UTS) gradually increase by 30% to 95% and 137% to 1020 MPa, respectively. At the lowest temperature of 4.2 K, the ductility keeps 65% and the UTS increases by 200% to 1300 MPa, which exceed those published in the literature, including conventional 300 series stainless steels. Detailed microstructural analyses of this alloy reveal a change of deformation mechanisms from dislocation slip and nano-twinning at 293 K to nano-phase transformation at 4.2 K. The cooperation and competition of multiple nano-twinning and nano-phase transformation are responsible for the superior tensile properties at cryogenic temperatures. Our study provides experimental evidence for potential cryogenic applications of HEAs. [Display omitted] [ABSTRACT FROM AUTHOR]

On the contrary to the common belief that glass formation is unfeasible near terminal intermetallic compound due to fast crystallization kinetics, here we present our findings that bulk metallic glasses are readily formed near intermetallic compounds, far away from the traditional region of glass forming near eutectics. While the intermetallic compounds themselves are not possible glass formers, bulk metallic glasses can be quenched compositionally neighboring the intermetallic compounds as close as 0.5 at.%. Taking binary Cu-Zr as a model system, the phenomenon of two optimum glass forming compositions sandwiching the corresponding intermetallic compounds (Cu 51 Zr 14 , Cu 10 Zr 7 , CuZr, CuZr 2 and Cu 8 Zr 3 ) is observed consistently. This new scenario of “intermetallic glass” is verified by the thermodynamic principle that the alloy liquids neighboring the intermetallic compounds possess lower Gibbs free energy than that of the compounds themselves. Furthermore, the sluggish crystallization behavior of these liquids provides an additional kinetic explanation. [ABSTRACT FROM AUTHOR]

TiAl-based composites reinforced with different high volume fractions of nearly network Ti 2 AlC phase have been successfully prepared by mechanical alloying and hot-pressing method. Their microstructure, mechanical and tribological properties have been investigated. Ti 2 AlC network becomes continuous but the network wall grows thicker with increasing the Ti 2 AlC content. The continuity and wall size of the network Ti 2 AlC phase exert a significant influence on the mechanical properties. The bending strength of the composites first increases and then decreases with the Ti 2 AlC content. The compressive strength of the composite decreases slightly compared to the TiAl alloy, but the hardness is enhanced. Due to the high hardness and load-carrying capacity of the network structure, these composites have the better wear resistance. And this enhancement is more notable at low applied loads and high Ti 2 AlC content. The mechanisms simulating the role of network Ti 2 AlC phase on the wear behavior and the wear process of TiAl/Ti 2 AlC composites at different applied loads have been proposed. [ABSTRACT FROM AUTHOR]

Ultra-high strength alloys with good ductility are ideal materials for lightweight structural application in various industries. However, improving the strength of alloys frequently results in a reduction in ductility, which is known as the strength-ductility trade-off in metallic materials. Current alloy design strategies for improving the ductility of ultra-high strength alloys mainly focus on the selection of alloy composition (atomic length scale) or manipulating ultra-fine and nano-grained microstructure (grain length scale). The intermediate length scale between atomic and grain scales is the dislocation length scale. A new alloy design concept based on such dislocation length scale, namely dislocation engineering, is illustrated in the present work. This dislocation engineering concept has been successfully substantiated by the design and fabrication of a deformed and partitioned (D&P) steel with a yield strength of 2.2 GPa and an uniform elongation of 16%. In this D&P steel, high dislocation density can not only increase strength but also improve ductility. High dislocation density is mainly responsible for the improved yield strength through dislocation forest hardening, whilst the improved ductility is achieved by the glide of intensive mobile dislocations and well-controlled transformation-induced plasticity (TRIP) effect, both of which are governed by the high dislocation density resulting from warm rolling and martensitic transformation during cold rolling. In addition, the present work proposes for the first time to apply such dislocation engineering concept to the quenching and partitioning (Q&P) steel by incorporating a warm rolling process prior to the quenching step, with an aim to improve simultaneously the strength and ductility of the Q&P steel. It is believed that dislocation engineering provides a new promising alloy design strategy for producing novel strong and ductile alloys. [ABSTRACT FROM AUTHOR]

The complex metallic alloy (CMA), Al 76.8 Fe 24 , was in-situ synthesized in the Al-based hybrid composite by powder metallurgy technique. The structural analysis by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy indicated that the Al 76.8 Fe 24 CMA phase was formed by diffusion of Fe atoms into the Al matrix during the sintering stage. The formation of the CMA phase was mainly determined by the sintering temperature which was just above the eutectic temperature of Al–Fe. Moreover, the fully dense Al-based hybrid composite was obtained and exhibited ultrahigh strength ∼1100 MPa, indicating that this method is expected to be effective in producing CMA particle reinforced Al-based hybrid composite. [ABSTRACT FROM AUTHOR]

Alloys, Anions, Chemicals, Dentistry, Electrochemicals, Health and Medicine, Phosphates, Phosphoric Acids Keywords: Alloys; Anions; Chemicals; Dentistry; Electrochemicals; Health and Medicine; Phosphates; Phosphoric Acids EN Alloys Anions Chemicals Dentistry Electrochemicals Health and Medicine Phosphates Phosphoric Acids 6097 6097 1 03/27/23 20230331 NES 230331 2023 MAR 31 (NewsRx) -- By a News Reporter-Staff News Editor at Health & Medicine Week -- Data detailed on alloys have been presented. [Extracted from the article]

Metallic materials and alloys may exhibit serrated flow, rate insensitivity or negative rate sensitivity in a certain range of strain, strain rate and temperature. This behavior is referred to as dynamic strain aging phenomenon. A rate-dependent nonlinear kinematic hardening model was proposed by Ho (2008 ) in order to model positive, zero, negative rate sensitivity of flow stress and other rate-dependent inelastic behavior in a consistent way. But it has not been demonstrated that the proposed model can be accommodated by the framework of thermodynamics of irreversible processes. The present contribution thus aims at thoroughly examining the thermodynamic consistency of the constitutive model. The evolution equations for the internal state variables are derived through the introduction of two potentials, the thermodynamic potential and the dissipation potential. [ABSTRACT FROM AUTHOR]

The article offers a process to sort out the challenge with sorting aluminum alloys using a handheld X-ray fluorescence (XRF) device. Topics discussed include use of XRF in alloy identification and sorting, challenges for aluminum grades such as surface contamination, and use of SmartSort, a sorter-friendly smart logic, for aluminum grades.

The article discusses the results of an investigation regarding the electrical properties, hardness and structure of 6101 grade AlMgSi alloy from Continuus-Properzi continuous casting and rolling line (CCR). It sys that AlMgSi alloy properties are formed in Continuus-Properzi CCR line by selection of alloying elements, CCR parameters and heat-mechanical treatment sequence. It adds that observation of AlMgSi alloy microstructure by scanning electron microscope use.

The article discusses several approaches for making multi-material vehicles to meet fuel economy and environmental issues including Alcoa's "Micromill" used for making any automotive structure, NHTSA (U.S. National Highway Traffic Safety Administration) sponsored Lightweighting Project suggested multi materials for different parts to attain optimum level. Another approach is decklid concept using TCA Ultra Lite and carbon fiber RTM making 40 percent weight reduction.

The article discusses materials research conducted in 2007 concerning the development and implementation of bulk metallic glasses (BMG). An overview of BMG is provided, describing its molecular structure and properties. The successful implementation of BMGs in space craft and high-performance sporting goods are highlighted.

The following Metal Bulletin noble alloys, bulk alloys and ores prices changed on Friday September 14: [ABSTRACT FROM AUTHOR]

Uncertainty about the fate of US sanctions against UC Rusal Plc have kept aluminium foundry alloy premiums up in the United States and Europe, with sellers able to wield control of 2019 supply contract negotiations thanks to buyers' dwindling inventories. [ABSTRACT FROM AUTHOR]

Concern and unease are spreading among noble alloys market participants over the implications of the UK's decision to leave the EU. [ABSTRACT FROM AUTHOR]

The author discusses the recycling solution being offered by Tipton, Indiana-based metal supplier High Performance Alloys Inc. for obsolete and old metals to match their niche specifications. He explains the metal recycling techniques used by the company to meet a customer's demand for a Hastelloy B alloy, including water quenching and independent chemical and mechanical analysis. He also emphasizes the commitment of the company to establish good relationships with its customers.

The article offers brief information on the X-MET8000 handheld (X-ray fluorescence) XRF analyzer for alloy identification from Oxford Instruments.

The article evaluates the Innov-X handheld analyzer with x-ray fluorescence manufactured by Ashtead Technology for positive material identification and quality control, metal cycling, and non-destructive testing

Reports on the development of CETSOL and IMPRESS programs designed to improve the understanding of gravity's effect on metalcasting and solidification at the University College Dublin in Ireland. Purpose of computer models in describing the characteristics of molten alloys; Focus of the IMPRESS program on intermetallics materials; Use of micro-gravity available in space for the investigations.

Features the XLi and XLt handheld X-ray fluorescence alloy analyzers manufactured by Niton LLC. Distinct features of the product; Usability of the product; Product offering.