Wear Behaviour of Crankshaft Journals Filled by Submerged Arc Welding

In this study, wear behaviour of crankshaft journals filled by a submerged arc welding with different welding wires and powders is investigated. Hardness and microstructure variations in the submerged arc welding are examined. In addition, the amount of weight loss in abrasion samples of filling dry and lubrication ambience is measured under 40 N loads. It is observed that the amount of abrasion decreased with the increase of hardness at a certain point. Thin wire structure is provided for better abrasion resistance, and abrasion decreases with lubrication.В работе исследован режим износа цапф коленчатого вала, обработанных дуговой сваркой под флюсом с различными сварочными проволоками и порошками. Изучены вариации твёрдости и микроструктуры при дуговой сварке под флюсом. Кроме того, была измерена величина потери веса в образцах, подвергнутых истиранию в сухих и смазочных средах при нагрузках в 40 Н. Наблюдалось уменьшение величины истирания с увеличением твёрдости до определённого предела. Было обеспечено использование тонкой проволоки для лучшего сопротивления истиранию, а истирание уменьшалось при смазке.В роботі досліджено режим спрацювання цапф колінчастого валу, оброблених дуговим зварюванням під флюсом з різними зварювальними дротами і порошками. Досліджено варіації твердості та мікроструктури при дуговому зварюванні під флюсом. Крім цього, було виміряно величину втрати ваги в зразках, підданих стиранню в сухих і змащувальних середовищах при навантаженнях у 40 Н. Спостерігалося зменшення величини стирання зі збільшенням твердості до певної границі. Було забезпечено використання тонкого дроту для кращого опору стиранню, а стирання зменшувалося при змащуванні

The effect of continuous and pulsed current on microstructure and mechanical properties in TIG welding of Al-Si alloy sheets

In this experimental study, Al-Si alloy sheets were joined through TIG welding method by using continuous current and pulsed current. Tensile test, bending test, hardness test, and microstructure examination of joined test samples were carried out in order to see the effect of current type on mechanical properties of welded samples. Experimental results showed that pulsed current led to low heat input, grain refinement, and hardness increase in weld metal compared to alternative current. The samples joined by using the pulsed current showed higher tensile strength than the samples welded by using the alternative current. After bending test, cracks, tearing, and surface defection were not observed in the samples

Weldability of Zinc Coated Automotive Steel Sheets by Resistance Spot Welding

APAY, Serkan/0000-0003-4624-9082WOS: 000208889900011In a given study, resistance spot welding of automotive steel sheets, which are widely used in the house-goods and car manufacturing industry, is studied. The shear strength, hardness and microstructure of the welded parts are measured in order to find the effects of welding period, welding current, and thickness of the galvanizing under constant applied electrode force pressure. Welding periods are chosen as 22 and 27 cycles, and welding current increased from 4.5 kA to 5.5 kA. The electrode-applied forces are kept constant at 3.5 Bar. The samples are exposed to tensile shear tests, hardness tests and metallographic examinations, and suitable welding parameters are advised to users. The results show that, increasing welding period and thickness of coating, the tensile shear strength and hardness of the welding nugget are increased

The Effect of Joining Process on Mechanical Properties of Structural Steels

Tuncer, Enis/0000-0002-9324-4324;WOS: 000285446000012Welding of structural steels is extensively used in various fields. In general, welding of these steels does not pose any problems. They may be welded with almost all well-known welding techniques. Different chemical contents of these steels and their joining methods may affect the mechanical properties and microstructure of the materials. In this study, AISI 1020-ASTM A514 steels have been welded by MMAW (MMAW manual metal arc welding), MIG (MIG-metal inert gas), MAG (MAG-metal arc gas) and TIG (TIG-tungsten inert gas) welding. Tensile tests, bending tests and hardness measurements have been carried out. The material microstructure has been investigated by means of optical microscopy in order to characterize the effect of processing parameters on the joints quality. The highest tensile strength and hardness values have been obtained for the MAG welded couples, while the lowest values have been obtained for the TIG welded materials. These changes have been explained with reference to the microstructure changes

The effect of cold and hot reformation process to mechanical properties of deformed automobile chassis material

Vehicles are damaged as a result of traffic accidents. Chassis and body parts of damaged vehicles are reformed by using cold and hot deformation methods. High-strength low alloy (HSLA) steel material coated (galvanised) with S320GD+Z quality (DIN EN 10326) zinc, which is used in chassis production, was used in this study. Steel sheet materials were damaged. Damaged automotive chassis material was reformed with cold and hot reformation processes. Tensile, notch impact, bending and hardness tests were applied to the reference material which were not deformed and materials to which reformation process was applied. In the light of obtained results, the effect of reformation process on mechanical properties of automotive sheet was determined