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Aims to determine if friction welding is suitable for welding austenitic stainless steel (AISI 304)

Uses an experimental continuous drive friction welding set‐up. Determined the strength, hardness and microstructure of the joined parts.

Finds that the joint strengths are 96 per cent of those of the base metals with no significant hardening.

Friction welding is an appropriate joining method for austenitic stainless steel (AISI 304).

Aids in understanding appropriate uses of friction welding for joining stainless steel.

The purpose of this paper is to evaluate temperature and properties at interface of AISI 1040 steels joined by friction welding.

In this study, AISI 1040 medium carbon steel was used in the experiments. Firstly, optimum parameters of the friction welding were obtained by using a statistical analysis. Later, the microstructures of the heat‐affected zone are presented along with micro hardness profiles for the joints. Then, the temperature distributions are experimentally obtained in the interface of the joints that is formed during the friction welding of 1040 steels with the same geometry. This study was carried out by using thermocouples at different locations of the joint‐interface. The results obtained were compared with previous studies and some comments were made about them.

It was discovered that temperature had a substantial effect on the mechanical and metallurgical properties of the material.

The maximum temperature in the joint during frictional heating depends not only on the pressure, but also on the temperature gradient which depends on the rotational speed in particular. It is important to note that the measurement process was successfully accomplished in this study although it was particularly difficult to obtain temperature due to the large deformations at the interface. Future work could be concentrated on the temperature measurement of the joined materials.

Temperature is one of the most important of all physical quantities in industry. Its measurement plays a key part in industrial quality and process control, in the efficient use of energy and other resources, in condition monitoring and in health and safety. This paper contributes to the literature about temperature measurement in welded, brazed and soldered materials.

The main value of this paper is to contribute and fulfill the influence of the interface temperature on properties in welding of various materials that is being studied so far in the literature.

The purpose of this paper is to determine the influence of surface roughness on materials flow of various materials using grid lines during cold forming.

The study is focused on the investigation of the influence of the surface roughness on the materials flow for different materials using grid lines in the upsetting. Stainless steel, SAE 1020 steel, commercially pure aluminum, commercially pure copper and CuZn₄₀Pb₂ brass are used as the test materials. Upsetting process is applied to the cylindrical specimens using the flat end dies. Strain distributions on the free surfaces of cylindrical upset specimen are measured for different upsetting reductions. Strain distributions on the free surfaces are obtained by the measurements of the dimensions of the square grid elements before and after the upsetting process. Experimental results are placed into graphical plots.

It is found that surface roughness is effectual on the strain changes on the free surfaces with the increasing deformation ratio for especially two types of steel specimens. There has been no considerable effect on aluminum, copper and brass specimens.

It would be interesting to search the surface roughness, R_sk and other parameters describing the bearing properties of the surface of more materials. Future work could be concentrated on the cold forming of these materials.

Different forming technologies are nowadays widely applied in mass production of mechanical components for needs of transportation, electronics, household appliances, etc. In order to reduce costs, manufacturers are trying to minimize additional machining and therefore to implement the influence of surface roughnesses on materials flow of various materials.

The main value of this paper is to contribute to studies on the influence of surface roughness on materials flow of various materials.

The main purpose of the present study was to evaluate the metallurgical and mechanical properties of dissimilar metal friction welds (FWs) between aluminium and type 304 stainless steel.

One of the manufacturing methods used to produce parts made from different materials is the FW method. Therefore, in the present study, austenitic stainless steel and aluminium parts were joined by FW. Tensile, fatigue and notch-impact tests were applied to FW specimens, and the results were compared with those for the original materials. Microstructure, energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analysis and hardness variations were conducted on the joints.

It was found from the microstructure and XRD analysis that inter-metallic phases formed in the interface which further caused a decrease in the strength of the joints.

In this study, the rotation speed was kept constant. The effects of the rotation speed on the welding quality can be examined in future. It is important to note that the FW process was successfully accomplished in this study although it was particularly difficult to obtain the weld due to the large deformations at the interface.

Low-density components such as aluminium and magnesium can be joined with steels owing to being cost-effective in industry. Application of classical welding techniques to such materials is difficult because they have different thermal properties. Their welding plays a key part in industrial quality and process control, in the efficient use of energy and other resources, in health and safety. Then, this study will contribute for welded, brazed and soldered materials.

The main value of this paper is to contribute and fulfill the influence of the interface on properties in welding of various materials that is being studied so far in the literature.

The purpose of this paper is to investigate mechanical and metallurgical variations at interfaces of commercial austenitic‐stainless steel and copper materials welded by friction welding.

In this paper, austenitic‐stainless commercial steel and copper materials are welded using the friction welding method. The optimum parameters are obtained for the joints. The joints are applied to the tensile and micro‐hardness tests. Then, micro‐ and macro‐photos of the joints are examined.

It is found that some of the welds show poor strength depending on some accumulation of alloying elements at the interface result of temperature rise and the existence of intermetallic layers.

It would be interesting to search about the toughness values and fatigue behaviour of the joints. It could be a good idea for future work to concentrate on the friction welding of these materials.

Friction welding can be achieved at high‐production rates and therefore is economical in operation. In applications where friction welding has replaced other joining processes, the production rate has been increased substantially.

The main value of this paper is to contribute to the literature on friction welding of dissimilar materials.

The present study seeks to examine the possibilities of combined usage of friction welding and plastic forming in recycling of bar‐shaped waste materials.

If the waste materials can be reproduced using various manufacturing methods without melting, their economic values could be increased economically. For this reason, using a combination of friction welding and plastic forming was chosen as an alternative recycling method. Upsetting was chosen as the plastic forming method due to its ease of application.

In the present study, dimensional changes, hardness variations in heat affected zone (HAZ), variations of torsion and tensile strengths with upsetting ratio of specimens were examined. Hardness values of test material are raised to higher levels within the HAZ by the local hardening. The maximum shear stress in torsion and the tensile strengths of specimens are closely harmonious with hardness values of test material.

Although it was observed in general that the increasing upsetting ratio increased the torsion and tensile strengths, experimental study must be improved and extended in order to obtain more precise results.

It can be concluded that combined usage of just welded and additional cold deformation can be considered as an alternative recycling method owing to obtained positive results.

This paper helps individuals reutilize waste materials because of the small lengths of the bars. Furthermore, it can be observed that the combination of friction welding and plastic forming produces savings in the material and the cost in this study.

In the presented study, AISI 1040 medium carbon steel and AISI 304 austenitic stainless steel parts were joined by friction welding. The welding process was carried out under optimized conditions using statistical approach. Tension tests were applied to welded parts to obtain the strength of the joints. Fatigue properties were additionally obtained experimentally under fluctuated tensile loads. Finally, notch impact tests were applied to the joints. Microstructures using microphotographs were examined in the heat affected zone of welded parts. Hardness variations in welding zone were also obtained. Experimental results were compared with those of previous studies.

Friction welding is a solid state bonding process, where the joint between two metals has been established without melting the metal. The relative motion between the faying surfaces (surfaces to be joined) under the application of pressure promotes surface interaction, friction and heat generation which subsequently results in joint formation. Stainless steel is an iron based alloy, contains various combinations of other elements to give desired characteristics, and found a wider range of applications in the areas such as petro‐chemical, fertilizer, automotive, food processing, cryogenic, nuclear and beverage sectors. In order to exploit the complete advantages of stainless steels, suitable joining techniques are highly demanded. The Friction welding is an easily integrated welding method of stainless steel, which considered as non‐weldable through fusion welding. Grain coarsening, creep failure and failure at heat‐affected zone are the major limitations of fusion welding of similar stainless steels. Friction welding eliminates such pitfalls. In the present work an attempt is made to investigate experimentally, the mechanical and metallurgical properties of friction welded joints, namely, austenitic stainless steel (AISI 304) and ferritic stainless steel (AISI 430). Evaluation of the characteristics of welded similar stainless steel joints are carried out through tensile test, hardness measurement and metallurgical investigations.

The purpose of this paper is to examine the effects of the welding deformation and surface roughness in cold pressure welding on the tensile strength and the fatigue strength of joined sheets. Additionally, the paper seeks to analyse the hardness variations and microstructures at the welding interface.

Cold pressure welding is a method of joining similar or dissimilar ductile metals. It can be applied by bringing into close contact the surfaces of virgin metal specimens that appear due to the breakdown of the surface layers caused by bulk plastic deformation. Cold pressure welding is applied to test parts without too long a delay after the preparation of surfaces. The application of welding in 10 min affects importantly the weld strength. As this time is increased, the weld strength of the joints is decreased. The determination of deformation amount is found by determination of the reduction (R) at the total thickness of the two parts after the welding process.

The weld strength increases as the surface roughness and weld deformation of the joined sheets increase. The length of bond zones increases with increasing deformation. Therefore, the weld strength of parts depends on the length of bond zones. Then, there is an effect of surface roughness on the welding strength. Joined sheets show resistance to little fluctuating tensile stress. It is observed that the parts rupture from the welding‐interface hardness values are about the same at interfaces of sheets having different surface roughness and equal deformation (60 per cent). But, if it is considered that hardness of aluminium material purchased is about 53 HV, it can be said that the hardness increases in joined parts because of local hardening during deformation in cold pressure welding method as lap welding. Bond formation at interfaces of joined sheets having R_a=5 μm surface roughness and deformation ratio 60 per cent is shown to be successful in the microstructure photo.

Surface roughness and deformation values can be increased in further studies.

The paper offers insight into the effects of surface roughness on weldability.

Most of the machine parts can be produced using several manufacturing methods, such as forging, machining, casting or welding. The type of manufacturing method may be selected with respect to production costs of the alternatives for individual parts. In the presented study, an experimental friction welding set‐up was designed and constructed in order to investigate the effects of some welding parameters on the welding quality. The set‐up was constructed as continuous‐drive. Several groups of specimen were machined from the same material. Some pilot welding experiments under different process parameters were carried out in order to obtain optimum parameters according to statistical approach. The strengths of the joints were determined by tension tests, and the results were compared with those of specimen's material. Addition to the tensile test data, hardness variations and microstructures in the welding‐ zone were obtained and examined.