Induction Heating Validation of Dieless Single-Point Incremental Forming of AHSS

Abstract

Advanced high-strength steel (AHSS) is subject to a high deformation in geometry due to spring-back and high forces during forming. Therefore, dieless single-point incremental forming supported by induction heating was introduced. When a HCT980C steel part was studied, it was observed that the geometrical accuracy increased by forming using a 15 kW induction power, whereas a high deviation in profile geometry was observed by forming using a 5 kW induction power. The forming forces decreased by 66.63% compared with those resulting from forming at room temperature. At the same time, the HCT980C steel part cracked and failed to reach its designed depth when forming at room temperature. Regulating the tensile strength and hardness of the formed part and preventing their reduction was achieved by increasing the feed rate continuously as a function of the formed part’s growing depth. Moreover, the distribution of the induction heating temperature was reduced by introducing the new forming strategy. A cone wall angle of 70° was flexibly formed from a HCT980C steel sheet when the new strategy was applied.

Keywords

• dieless single-point incremental forming
• induction heating
• geometrical accuracy
• formability