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In this study, holes were drilled on the Sleipner cold work tool steel with a hardness of 60-62 HRC by copper and brass electrodes using three different current values (50, 25, 12.5 A), pulse on times (3, 6, 9 μs) and pulse off times (4, 6, 8 μs) parameters in the EDM method; the effects of these working parameters on machining times, material removal rate (MRR), electrode wear rate (EWR), the hole inlet-outlet diameters of the machined parts, the kerf on workpiece and electrode were analyzed. As a result of the analyzes made, in the use of copper electrodes, the MRR increased by 311.25% on average compared to the use of brass electrodes, while the EWR and machining time decreased by 42.01% and 38.46%, respectively. The increase in sparking and thermal effects between the workpiece and the electrode resulted in an increase in the MRR and a decrease in the machining time. In the use of copper and brass electrodes with different processing parameters, the inlet diameters of the drilled holes were found to be larger than the outlet diameters as well as an irregular kerf formation was observed due to debris evacuation due to worn electrodes.

Purpose This study aims to systematically compare the effect of increasing fiber–matrix interface adhesion and matrix toughness in layered composite materials. Design/methodology/approach Silane ((3-glycidyloxypropyl) trimethoxysilane) was applied to strengthen the fiber–matrix interface connection in e-glass/epoxy laminated composite material. Using a cationic surfactant, 0.1% multi-walled carbon nanotubes (CNTs) were added to the matrix in two different ways, by with and without chemical functionalization using the vacuum infusion method. Findings In the results obtained from the three-point bending test specimens, it was determined that the synergistic effect of silane application and non-functionalized CNT in the matrix was higher in terms of flexural modulus and strength values. Practical implications The functionalization of multi-walled CNT did not give the expected results because of reasons such as viscosity increase and agglomeration in the matrix. Originality/value In this study, a simple model for normalization and prediction purposes was developed, which allows the determination of the flexural modulus and un-notched flexural strength values from one test result of the notched specimen. A systematic comparison was performed by varying each parameter in the composite material.

Bu çalışmada konvansiyonel yöntemlerle delinmesi maliyetli ve zor olan yüksek sertlikteki (60-62HRC) X153CrMoV12 soğuk iş takım çeliğine elektro erozyonla hızlı delik delme tezgahında 3 mm pirinç elektrotlar kullanılarak delikler delinmiştir. Bu kapsamda üç farklı amper (5, 6, 7 A), üç farklı voltaj (1, 2, 3 V), altı farklı ark süresi (18, 22, 24, 26, 28, 29 μs), dört farklı bekleme süresi (3, 6, 8, 10 μs) parametrelerinin işleme süresi ve delinen deliklerde oluşan kerf üzerine etkileri makro analizler ve analitik ölçümlerle tespit edilmiştir. Yapılan analizler neticesinde kerf açısına ve işleme zamanına etkisi en yüksek parametrenin işleme akımı olduğu tespit edilmiştir. Akım, voltaj ve ark süresinin artması işleme süresini azaltırken, bekleme süresinin artmasıyla işleme süresi artmıştır. Genel olarak elektrot malzemesinin içerisinden ve dışarısından dielektrik sıvı püskürtülmesiyle aşınan partiküllerin ortamdan tahliye edilmesine bağlı olarak işleme parametrelerinin kerf üzerinde doğrusal olmayan bir etki yaptığı tespit edilmiştir. En düşük kerf açısı ve en yüksek işleme süresine maksimum akım değeri 7A, 3V voltaj, 29 μs ark süresi ve 3 μs bekleme süresi çalışma parametreleri kullanılarak ulaşılmıştır. Ayrıca delik giriş çapında 170 μm, çıkış çapında ise 220 μm boyutsal tamlık elde edilmiştir., In this study, holes were drilled on X153CrMoV12 cold work tool steel with high hardness (60-62HRC), which is difficult and costly to drill with conventional methods, using 3 mm brass electrodes on a fast hole drilling machine by electro-erosion. In this context, the effects of three different amperes (5, 6, 7 A), three different voltages (1, 2, 3 V), six different pulse on-time (18, 22, 24, 26, 28, 29 μs), four different pulse off-time (3, 6, 8, 10 μs) parameters on the processing time and the Kerf formed in the drilled holes were determined by macro analysis and analytical measurements. As a result of the analysis, it has been determined that the parameter with the highest effect on the kerf angle and machining time is the machining current. The processing time increased with the increase of the pulse off time on the other hand the increase in current, voltage and pulse on time decreased the machining time. In general, it has been determined that the processing parameters have a non-linear effect on the kerf due to the pressure flushing of dielectric liquid from the inside and outside of the electrode material, and the evacuation of the abraded particles from the environment. The lowest kerf angle and the highest processing time were achieved using the operating parameters of 7A maximum current, 3V voltage, 29 μs pulse on time and 3 μs pulse off time. In addition, a dimensional accuracy of 170 μm in the hole inlet diameter and 220 μm in the output diameter was obtained.

Refractory high entropy alloys (RHEAs) with multiple principal elements constitute a new paradigm in alloy design and have gained recent interest for advanced technical applications due to their unique properties and mechanical stability at high temperatures. However, the refractory metals that make up these alloys are pretty expensive, and they cause RHEAs to exhibit low plasticity behaviour at room temperature. The high stability properties of RHEAs from room temperature to high temperatures limit their machinability with traditional cutting methods. Therefore, it is vitally important to economically machine these alloys while preserving their mechanical properties and minimising waste. For this purpose, in this study, the machinability of a HfTaTiVZr RHEA was evaluated with wire electric discharge machining (WEDM). The surface morphology, crack formation, and mechanical characteristics of the surface layer were investigated as a function of three different cutting conditions: rough cutting, semi-finishing, and finishing. The RHEA was precision cut in three passes by reducing the volume of material in each pass, resulting in better surface quality with the optimal cutting speed and metal removal rate. However, rough cutting gave better results than semi-finish and finished cutting processes in preserving mechanical properties.

Refractory high entropy alloys (RHEAs) have shown great promise for a multitude of advanced engineering applications due to their high mechanical stability from cryogenic temperatures to 1600 °C. However, the low ductility they exhibit at room temperature limits their machinability when traditional machining techniques are used. Studies on the nontraditional machining of RHEAs, on the other hand, are very limited. In the present work, MoNbTaTiZr RHEAs subjected to wire electrical discharge machining (WEDM) were examined using electron microscopy, contact profilometry, and nanoindentation. Voids, microcracks, and recast material were observed on the machined surfaces. A transition from roughing to finishing decreased the amount of recast material, but the density of observable voids and microcracks on the surface increased. Optimal results were obtained by finishing, where the surface quality was improved by the removal of recast material remaining from prior passes. The brass wire electrode provided a smoother surface while the copper-core electrode provided minor heat-affected zone in the MoNbTaTiZr samples. In the roughing cuts, a 7.00% improvement in surface roughness was achieved using the copper-core electrode compared to the brass electrode. In the semi-finishing and finishing cuts, the brass wire electrode provided improvements of 13.68% and 22.68%, respectively, compared to the copper-core electrode. On the other hand, the wear of the brass electrode was as much as 20.98% higher than that of the copper-core electrode.

Inconel 718 alloy is difficult to machine using conventional methods due to its physical properties. Thereby, additive manufacturing (AM) of IN718 components with near-net shapes has been excessively studied. Even though AM processes provide shape and size accuracy, there is still the need for the machining of the AM-processed components. Laser powder bed fusion (LPBF) has been successfully utilized to fabricate near-net shape IN718 components, moreover, the microstructure of LPBF-IN718 was unique owing to the AM processing, resulting in differences in grain size, grain boundary characteristics, and grain orientations. Furthermore, these microstructural characteristics are expected to alter the machining performance of IN718. Therefore, this study investigated the wire electro-discharge machining (WEDM) performance of LPBF-718 samples compared to wrought IN718 while focusing on the unique microstructure characteristics of LPBF-IN718 samples (lamella, single-crystal, ploy-crystal). Three different cutting strategies (rough, semi-finish, and finish) were implemented to understand the performance of the multi-pass cutting phenomenon and its effect on the surface of IN718. For all samples, rough (single pass) cutting displayed high roughness while finish (three passes) cutting exhibited good surface quality. Compositional analyses on the machined surface showed debris formation including Zn and Cu-containing recast material, indicating wire erosion. The surface of single-crystal LPBF-IN718 after the WEDM process was smooth owing to its big grain size and less amount of grain boundary, resulting in slow cutting speed but a good surface finish. Thus, this study, for the first time, investigated the effect of unique microstructural characteristics of LPBF-fabricated IN718 on WEDM performance and machined surface quality.

Üretildikleri 1950’li yıllardan beri havacılık, uzay, nükleer, biyomedikal endüstrisi gibi ileri mühendislik uygulamalarında sıklıkla tercih edilen Inconel grubu alaşımların daha maliyet etkenli bir yöntem olan eklemeli imalat yöntemiyle üretilebilirliği son 20 yılda yoğun olarak çalışılmaktadır. Ancak, süper alaşımlar işlenebilirliği zor malzemeler grubunda olup, iletkenlikleri zayıf olduğundan bu alaşımların delinmesinde kullanılan elektrotlarda ciddi hasarlar meydana gelmektedir. Dahası, eklemeli imalat yöntemiyle üretilen bu alaşımların delinebilirliğinde kullanılan elektrotlardaki aşınmayı inceleyen sınırlı sayıda çalışma vardır. Bu amaçla bu çalışmada, dövme ve eklemeli imalat tekniği ile üretilmiş Inconel 625 alaşımların, EDM ile hızlı delik delme yöntemi kullanılarak 3 mm çapında pirinç elektrotlarla delinmesi neticesinde aşınan elektrotlarda oluşan aşınma miktarları incelenmiştir. Elektrot aşınması; iş parçası üzerinden ölçülen delik çapları ve kerf açıları dikkate alınarak analitik olarak ve deneylerde aşınan elektrotların hassas terazilerle tartılması ile fiziksel olarak tespit edilmiştir. Daha tok ve kararlı bir yapıda olan dövme Inconel malzemeyi işleyen elektrodun eklemeli imalat Inconel alaşımı işleyen elektroda göre % 108,33 daha fazla aşındığı tespit edilmiştir. Buna ilaveten, dövme Inconel iş malzemesinde elektrot aşınmasından kaynaklı kerf açısının eklemeli imalat Inconel malzemeye göre % 80,06 daha fazla olduğu görülmüştür.

In this study, metal was removed by electro erosion processing method using Copper Chromium Zirconium Alloy Electrode from Sleipner Cold Work Tool Steel with 60-62 HRC hardness value. In this context, experiments were carried out using three different discharge currents (6,25; 12,5; 25 A), three different pulse on times (3; 6; 9 µs), three different pulse off times (4; 6; 8 µs). The effects of the used processing parameters on the fundamental performance outputs such as surface roughness, kerf angle, processing time were determined by analytical measurements and macro analysis. As a result of the analysis, the processing time increased significantly with the increase in the pulse off time and decreased with the increase of the working current and pulse on times. The increase in the working current increased the spark between the workpiece and the electrode, increasing the point melting and evaporation, as a result of which the surface roughness increased. The electrode was worn out due to the effect of the low pulse on time and high pulse off time parameters, as it worked more per unit time, as a result of this wear, the average kerf angle increased. As a result of the % 100 and % 300 increase in the discharge current, the average surface roughness increased by % 62 and % 87, respectively. Failure to evacuate debris and residues caused by wear of both the workpiece and the electrode material during EDM or sticking to electrode tips were caused irregularity in the processing time, surface roughness and kerf formation due to electrode wear., Bu çalışmada 60-62 HRC sertlik değerine sahip Sleipner Soğuk İş Takım Çeliğinden Bakır Krom Zirkonyum Alaşımı Elektrot kullanılarak elektro erozyon işleme (EEİ) yöntemi ile talaş kaldırılmıştır. Bu kapsamda üç farklı boşalım akımı (6,25; 12,5; 25 A), üç farklı ark süresi (3; 6; 9 µs), üç farklı bekleme süresi (4; 6; 8 µs) işleme parametreleri kullanılarak deneyler gerçekleştirilmiştir. Kullanılan işleme parametrelerinin yüzey pürüzlülüğü, kerf açısı, işleme süresi gibi temel performans çıktıları üzerindeki etkileri analitik ölçümler ve makro analizler ile belirlenmiştir. Yapılan analizler neticesinde bekleme süresinin artması ile işleme süresi büyük ölçüde artmış boşalım akımının ve ark süresinin artması ile azalmıştır. Boşalım akımının artması iş parçası ve elektrot arasında kıvılcımlanmayı arttırarak noktasal erime ve buharlaşma arttırmıştır bunun neticesinde yüzey pürüzlülüğü artmıştır. Düşük ark süresi ve yüksek bekleme süresi elektrotu birim zamanda daha fazla çalıştırarak aşındırmış bu aşınma sonucunda ortalama kerf açısı artmıştır. Boşalım akımının % 100 ve % 300’lük artışı neticesinde ortalama yüzey pürüzlülüğü sırasıyla % 62 ve % 87 oranında artmıştır. EEİ esnasında hem iş parçasının hemde elektrot malzemesinin aşınmasıyla ortaya çıkan debris ve kalıntıların ortamdan tahliye edilememesi veya elektrot uç kısımlarına yapışması işleme süresinde, yüzey pürüzlülüğünde ve elektrot aşınmasına bağlı kerf oluşumunda düzensizliğe sebep olmuştur.

Endüstride başta otomotiv ve beyaz eşya sektörlerinde yaygın olarak kullanılan özdeş ve imalat sayısı yüksek olan metal, plastik ve kompozit malzemelerin delinmesinde saç metal kalıpları tercih edilmektedir. Gelişen teknoloji, artan üretim kapasitesi ve rekabet koşulları imalatçıları daha az maliyetle daha fazla üretim yapmaya ve üretim proseslerini iyileştirmeye teşvik etmektedir. Bu çalışmada ÇCKNT katkılı ve katkısız CETP kompozit malzemelere 0.025 mm, 0.10 mm, 0.15 mm kesme boşluğu bulunan kalıplarda kaplamasız ve TiN kaplamalı zımbalar ile delik delinerek kesme kuvveti değişimi incelenmiştir. Yapılan çalışma neticesinde TiN kaplamalı zımba kullanılarak yapılan delme işlemlerinde ihtiyaç duyulan ortalama kesme kuvveti’nin kaplamasız SBZ zımba kullanımına göre katkılı ve saf kompozitlerde sırası ile % 10.10 ve % 4.50 oranında azaldığı tespit edilmiştir. Ayrıca kalıp üzerinde bulunan kesme boşluğunun azalması ile kesme kuvveti ihtiyacının arttığı ölçülmüştür.

İmalat sektörlerinde pul ihtiyacı genellikle zımba ve kalıp sistemleri kullanılarak karşılanmaktadır. Bu sistemlerde istenilen pul çapı kalıp mühre çapına işlenmekte, zımba çapı ise kesme boşluğu ölçüsü kadar küçültülerek delme işlemleri kalıp veya aparatlar üzerinde yapılmaktadır. Bu çalışmada ÇCKNT (çok cidarlı karbon nanotüp) katkılı ve katkısız CETP (cam elyaf takviyeli polimer) kompozit malzemelere 0.16 mm kesme boşluğu bulunan kalıplarda 90°, 15°, 30°, V, C tipi kesme formu bulunan Ø8 mm'lik zımbalar ile delik delinerek elde edilen pullar incelenmiştir. Yapılan çalışma neticesinde elde edilen pulların zımba kesme formunu aldığı, katkısız kompozitlerin 90° düz formlu zımba ile delinmesinde elde edilen pul çapının zımba ve mühre çapına göre sırasıyla % 4.75 ve % 0.72 oranında daha büyük ölçüde olduğu tespit edilmiştir. Ayrıca CETP kompozit malzemelere ÇCKNT katkısı malzemelerin dayanımını arttırarak zımba ile kesilmesi neticesinde elde edilen pulların daha rijit olmasını sağlamıştır. Bu sebeple katkılı kompozitlerin pul çapının zımba çapından büyük, mühre çapından küçük olduğu tespit edilmiştir.

Purpose The purpose of this study is to obtain strong materials with multiwall carbon nanotubes (MWCNTs) doped and investigate laser cut of MWCNTs also find the effect of the laser cutting parameters on composite materials. Design/methodology/approach The laminated composite plates were manufactured by using a vacuum infusion process. The mechanical properties of the composite materials produced were determined according to American Society for Testing and Materials (ASTM) D3039M, ASTM D3171, ASTM D 792 and ASTM D2583. A 130 Watts carbondioxide (CO2) laser cutting machine was used for drilling the two different composite plates with a thickness of 1.6–1.5 mm. Three variables were considered as process parameters including laser power (in three levels of 84.50, 104.00 and 127.40 W), cutting speed (in three levels of 4, 6, 8 mm/s) and 14 mm fixed focal position. Findings The fibers could not be cut due to insufficient melting in the experiments performed using 84.50 and 104.00 W laser power but the cutting was successfully completed when the laser power was 127.40 W. However, as the cutting speed increased, the contact time of the laser beam with the material decreased, so the kerf decreased, but the increased laser power created a thermal effect, causing an increase in hardness around the cutting surface. This increase was lower in MWCNTs doped composites compared to pure composites. It has been found that the addition of nanoparticles to layered glass fiber composite materials played an effective role in the strength of the material and affected the CO2 laser cutting quality. Originality/value This study is a unique study in which the CO2 laser cutting method of MWCNT-doped composite materials was investigated and the machinability without cutting errors, such as delamination, splitting, distortion and burring using the most suitable laser cutting parameters was revealed.

Purpose Wire electric discharge machining (WEDM) is a non-conventional machining process, which is used for cutting parts of civil and military aircraft, rotorcraft, satellites and spacecraft. The cold work steel X153CrMoV12 is used in molds that are needed to produce plastic and metal parts used in these areas. It is only possible to produce parts with precise dimensions and quality with the use of mold steels with sensitive surfaces. The purpose of this study is to analyze X153CrMoV12 material by cutting it with WEDM method in precise dimensions. Design/methodology/approach The effects of varying cutting parameters on the size of the finished product, surface roughness (SR) and surface hardness were determined by making rough in one pass and precision cuts in different passes. Nikon SMZ745T, Mitutoyo micrometer, Mitutoyo SJ-210 and Insize ISHL-P100 were used for macro-analysis, dimensional control, SR and surface hardness, respectively, to determine the cut qualities. Findings According to the hardness measurement results obtained from the steel surface before cutting and from the cut surfaces after cutting, there was no significant change in the surface hardness owing to the use of heat-treated steel. Increasing the wire tension as a result of the increase in the number of cutting passes and the decrease in the amount of rough stock left for the final cut increased the cut quality. Cutting precision has increased by preventing vibration of the wire with zero upper and lower water pressure required for slag cleaning. Originality/value There are many studies on WEDM in the literature, but there is no similar study emphasizing the importance of the processing parameters such as the number of cutting passes and rough stock amount. In this study, cold work steel with a hardness of 56–60 HRC was machined as rough cut in one pass, rough and fine cut in double pass, double fine cut after one roughing in three passes. As a result of the cuts, 3 µm measurement precision and 0.998 Ra SR were obtained as well as there was no hardness change in the cut surfaces.

In this study, the holes of glass fiber reinforced polymer (GFRP) and multi-walled carbon nanotubes (MWCNTs) doped GFRP composite materials were drilled using abrasive water jet (AWJ), CO2 laser cutting, orbital drilling, and punching methods; the effects of these methods on hole quality were determined. The hole entry and exit dimensions were obtained equal and in the desired size by orbital drilling; thus, kerf formation was prevented due to the lateral and face milling of the end mill. The surface hardness change was not observed in the hole circles obtained with the orbital drilling and punching methods. However, epoxy hardening was observed in the hole circles obtained by laser cutting due to the heat effect of laser beam. In AWJ method, matrix-fiber integrity was disrupted, and delamination was observed due to the effect of water pressure and kinetic energy; consequently an increase in material thickness was observed and surface hardness decreased. It was determined that MWCNTs additive increased the surface hardness of composites and maintained its hardness and durability in post-cutting measurements. Splintering and burring were not seen in any method, but fiber carbonization was observed in the inner parts of the hole due to thermal effects in laser cutting.

In this study, the effect of adding nanosize additive to glass fiber reinforced composite plates on mechanical properties and surface milling was investigated. In the light of the investigations, with the addition of MWCNTs additive in the composite production, the strength of the material has been changed and the more durable composite materials have been obtained. Slots were opened with different cutting speed and feed rate parameters to the composite layers. Surface roughness of the composite layers and slot size were examined and also abrasions of cutting tools used in cutting process were determined. It was observed that the addition of nanoparticles to the laminated glass fiber composite materials played an effective role in the strength of the material and caused cutting tool wear.

Wire electric discharge machining (WEDM) is widely used in dies, punches, aerospace and automotive sectors, since materials with high hardness, and temperature resistant, which are not possible to be cut with conventional machining methods, can be cut with high precision using the WEDM method. In this study, cutting speed (mm/min), material removal rate (mm3/min), wire consume (g), machining time (sec), finish measure (mm) and surface roughness (µm) changes as a result of cutting high hardness cold work tool steel using copper and brass wire in WEDM method were investigated. In addition, worn wire and workpiece residues on the machined surfaces were detected by SEM (Scanning Electron Microscope) and EDX (Energy Dispersive X-Ray) analyzes as well as topography and composition were examined. In the case of using copper wire instead of the brass wire, wire consumption and processing time decreased by 23.30 % and 66.29 %, respectively, while MRR increased by 50 % because the copper wire electrode has higher electrical and thermal conductivity than brass wire electrode. In addition, the average dimensional deviation of the parts cut with copper wire decreased from 27 μm to 8 μm compared to the use of brass electrodes, and more precise measurements were obtained.

Endüstride malzemelerin cıvata, perçin ve pim bağlantıları ile montajlanması veya üzerlerine delikler oluşturmak için matkap ile delme yöntemi kullanılmaktadır. Kompozit malzemelerin delinmesi esnasında çapaklanma, delaminasyon ve malzeme yarılması görülmektedir. İşleme parametreleri, delinen malzemenin mekanik özellikleri ve matkap nokta açısı delik kalitesini etkileyen en önemli faktörlerdir. Bu çalışmada cam elyaf takviyeli polimer (CETP) kompozit plakalara nano boyutta katkı maddesi eklenmesinin mekanik özelliklerine ve matkap yöntemi ile delinmesine etkisi araştırılmıştır. Tabakalı cam elyaf kompozit malzemelere nano partikül ilavesinin malzemenin dayanımında etkili bir rol oynadığı ve delik kalitesine etki ettiği görülmüştür. Sabit fener mili devri değerleri kullanılarak yapılan delme işlemlerinde; tezgah ilerlemesi arttıkça çapaklanmanın arttığı, matkap nokta açısının artması ile delik çapının arttığı tespit edildi. 90° ve 140° açılı matkaplar kullanılarak delinen deliklerin çıkış kısımlarında epoksi tabakasının blok şeklinde cam elyaf tabakasından ayrıldığı görüldü.

In this study, it was aimed to analyze the effects of machining parameters on the process quality by drilling holes in heat treated cold work tool steel with a hardness of 60-62 HRC using the electrical discharge machining (EDM) method and Ø2 mm diameter brass electrodes. In this context, drilling was performed using three different current values ​​(5, 6, 7 A), three different voltage values ​​(1, 2, 3 V), three different discharge pulse frequency Ton (23, 26, 29 µs) as well as Toff (3, 5 µs) respectively, and the effects of these machining parameters on the machining time, material removal rate (MRR), electrode wear rate (EWR), surface roughness (SR) and hardness of around the white layer were analyzed using micro, macro and analytical measurements, especially with Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDX). As a result of the analysis, ıt was observed that current, voltage, Ton and Toff had an effect on machining time, MRR, EWR, SR and hardness, but current was the most effective parameter, and also worn electrode as well as workpiece residues affected the process quality. Increasing the machining current increased sparking between the workpiece and the electrode, resulting in increased point melting and evaporation, resulting in increased average surface roughness, metal removal rate, and electrode wear rate. As a result of the high metal removal rate, the machining time was greatly reduced and the thermal effect time was reduced, which led to a decrease in the hardness variation on the machined surfaces.

The aim of this work is to investigate the effect of the hexagonal nano boron nitride (h-BN) doped epoxy on the mechanical performances and machinability behaviors of basalt fiber (BF) composites. The h-BN has used as a dopant with a weight rate of 1 wt. %. The polymer composites were prepared by the vacuum bagging method and specimens were processed with abrasive water jet machining (AWJM) to analyze the machinability of the material. A circular hole with an 8 mm size was machined by abrasive water jet (AWJ) on the composite plate with a thickness of 2.3 ± 0.1 mm using the garnet size of 80 µm as an abrasive. Taper angle and circularity of machined hole, the entry-exit hole diameter, delamination, splintering, burring, thickness, and hardness were measured. Results indicate that cutting speed has a high influence on the taper angle and circularity respectively.

WOS: 000510107300008, In this study, cutting of multi-walled carbon nanotubes (MWCNTs)-doped composite sheets by abrasive water jet machining (AWJM) and the effects of the water jet on cut composite materials were analyzed. The influence of MWCNTs doping to glass fiber-reinforced polymer composite plates was investigated. In addition, mechanical properties of doped composite and the effects of cutting by AWJM method were determined. It has been found that the addition of nanoparticles to layered glass fiber composite materials plays an effective role in the strength of the material and affects the abrasive water jet (AWJ) cutting quality. Additionally, composite materials were drilled using different water jet cutting parameters such as cutting speed, fixed nozzle diameter, cutting pressure and abrasive garnet. The entry-exit hole diameter, kerf, delamination, splintering, burring, thickness and hardness change were investigated. As the cutting speed increased, rotational slip, cutting start point, circularity and circular error increased. The thickness of the composites cut by water jet method increased and surface hardness decreased due to delamination. As the cutting speed increased, the hole inlet and outlet dimensions increased, which leads to an increased in size of the kerf.