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This paper is focused on single point incremental forming (SPIF) of a tailored welded blanks (TWBs) that produced by laser welding process. The SPIF process is a new dieless forming technology, which is a fast and economic solution to prototyping a metal sheet product. In the past, the SPIF researches carried out with the homogeneous metal sheet blank, but now a day, the demand of TWBs is still increased especially for an automotive industry. The aim of this research is to study the formability on the weld line of laser welding TWBs (SUS 304 and St 37) by the SPIF process.

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In hot forging process, the common failure modes of forging die are wear, fatigue fracture and plastic deformation. Normally die wear is occurred the most frequently and it influents directly to shape, dimension and surface quality of product. For this research, the hot forging process of idle gear was studied to focus on die wear. This product is forged in three steps. There are preform step, rougher step and finisher step. Height of preform shape in preform step was a parameter to study effect on die wear. Archard’s wear model in finite element modeling was used to predict die wear. The finite element modeling was verified by real hot forging process for reliable model and then it was used to determine the optimum preform height to reduce die wear. Finally the result showed that the maximum wear depth on the forging die was reduced 41.2% from original industry process.

Nickel-base superalloys are used as a land-base turbine engine due to its excellent properties at elevated temperatures. Nickel base superalloy, grade IN-738. Laser welding is commonly chosen for the refurbishment of the turbine blade. This paper aims to focus on understanding welding speed parameters in laser welding method. With constant power at 400 watts, welding speeds were varied from 1, 3, 5, and 8 mm/s. All of these alloys have no cracks found in fusion zone, HAZ, and bulk area. Increasing welding speed results in less heat energy input, reduces the penetration depth and weld pool area. The 1mm/s, which were subjected to the highest heat energy input, results in very small size of the γ’ precipitates in the fusion zone due to re-precipitation of the γ’ precipitates during the solidification process. The fusion zone also exhibits the highest hardness. The size of the γ’ precipitates in HAZ area are much larger, compared to the fusion zone The bulk areas have no effect from the heat and showed much larger size of the γ’ precipitates, which was caused by microstructural degradation during service, leads to the lowest hardness value among the three zones.