The joining of powder metallurgy products is of importance because of high demand in many industrial applications. In this study, the effect of welding voltage on the joint quality has been investigated using discharge arc stud welding, a low heat input welding method, without gas protection to join steel stubs to microwave sintered compacts containing a powder mixture of 26 atomic % Al and Fe (balance). It has been shown that welds with steel stubs are prone to side cracking in the weld zone and they also suffer from the oxidation of metal powders adjacent to weld zone. The forms of oxides are continuous and laminar type in welds with steel stubs and the composition of weld zone changes with increasing arc voltage.
In this study, a composite containing WC (Tungsten Carbide) and Ni was produced by two different processing routes. Electroless Ni coated WC powders were consolidated and sintered at 1200 • C. Diffusion bonding couples of WC(Ni)-electrolytic Cu, WC(Ni)-AISI 316 stainless steel and WC(Ni)-WC(Ni) were manufactured by using a preloaded compression system under Ar atmosphere. Diffusion bonding was carried out at varying bonding temperatures; 750 • C for (WC)Ni-Cu diffusion couple and 1200 • C for (WC)Ni-(WC)Ni and (WC)Ni-AISI 316 stainless steel diffusion couples. Standard metallographic techniques, Scanning Electron Microscopy and a shear test were employed to characterize the microstructure of bondline and mechanical properties of each diffusion couple, respectively.
Research on reducing the weights of automobiles, achieving
fuel consumption and reducing harmful exhaust emissions focuses on the
investigation of new materials. Polymer matrix is the most commonly used
material with respect to composite applications within the scope of
abovementioned research domain. Since polymer materials are inexpensive and
have improved physical and mechanical properties, they are used as a
substitution to metallic materials in several applications. The front barrier
of a car made of glass fiber-reinforced polymer composite is capable of
succeeding a crash test of 35-mph.
Besides providing a similar level of crash security as steel, polymer
composites are also capable of providing improved performance with features
such as vibration control. The use of polymer materials in the interior and
exterior design of automobiles increases each day. Polymer materials are preferred for various
car parts, such as consoles, door baffle boards, floor mats, air conditioning
pipes and grids etc. The present study focuses on the analysis of the
mechanical properties of polypropylene used in front consoles of the vehicles.
In this respect, front consoles of various automobile models, which were made
of polypropylene, were analyzed.
Anahtar kelimeler Fe 3 Al intermetalikler FeAl intermetalikler, saplama kaynağı, paslanmaz çelik, çelik, Alüminyum alaşımı Özet Fe-Al intermetalik malzemeler, seramikler ve metallerin sahip olduğu karakteristik özelliklere sahip olan bir malzeme sınıfıdır. Yüksek sıcaklık dayanımı ve oksidasyon dirençleri intermetalik malzemeleri yüksek sıcaklıkların söz konusu olduğu dizaynlar için en iyi aday malzemeler haline getirmiştir, fakat üretimlerinin zor oluşu ve kaynak kabiliyetlerinin kötü oluşundan dolayı Fe-Al intermetalik malzemelerin mühendislik malzemeleri olarak kullanımı sınırlı kalmaktadır. Bu çalışmada, Fe26Al, Fe30Al, Fe33Al ve Fe50Al intermetalikleri ark ergitme yöntemi ile üretilmiştir. Bu malzemeler kondansatör Deşarjlı Saplama kaynağı yöntemiyle farklı kaynak gerilimleri kullanılarak Ø 4 mm çapında paslanmaz çelik, alüminyum ve çelik saplamalarla birleştirilmiştir. Üretilen Fe-Al intermetaliklerin mikroyapı ve XRD analizleri yapıldıktan sonra kaynaklı bölgelerin de analizleri yapılmıştır. Bununla birlikte kaynaklı birleştirmelerin mekanik testleri yapılarak en yüksek mukavemetin Fe26Al intermetalik malzeme ile paslanmaz çelik saplama kaynağında oluştuğu gözlemlenmiştir.
In this study, MAG welding method was used. 2 mm thick TRIP 800 steel sheets are used in different welding parameters. Microstructures of welded joints were analyzed by taking OM (optical microscope) images from the main metal areas of the welding zone, HAZ (the region under the influence of heat). Depending on the welding parameters, (welding current: 40-50-60 Ampere, and welding speed: 5-7.5 mm/sn), ferritic, HAZ and martensitic phase regions were determined in microstructures in the main metal, HAZ and welding regions, respectively. The strengths of the welded connections were measured using the tensile test. Welding wire speed is chosen to obtain high penetration and ideal width welding seams. The strength of the welded bond using these parameters is determined as 1266 MPa as the highest value. It was determined that grain growth and martensitic phase transformations occur in fusion regions and result in brittle fracture. The Fusion zone and other regions were analyzed with finite elements.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.