No abstract

No abstract

In sheet metal forming, rapid cooling of austenitized steel and CRP (cushion-ram pulsation) results in an optimized formability. An analysis is conducted regarding the influence of a stepwise deep drawing process of manganese-boron steel 22MnB5, using an oscillating ram-cushion motion at simultaneous cooling. The stops occurring in stepwise forming provide sufficient time for softening and recovery of forming properties. The microstructure can be adjusted by controlled cooling. In order to examine the newly developed process in more detail, FE simulation is applied. Thus, relevant process and material parameters can be determined. The considered values are required for profound experiments using the forming simulator BAEHR DIL 805 A/D. The softening behavior at defined forming temperatures due to CRP are examined. The experimental results of softening at distinctive temperatures provide a basis for the combined processes of stepwise hot sheet metal forming and simultaneous cooling.

This paper presentsa technique for selective and energy-efficient induction heating of aluminum (Al) frames to support and enhance the thermocompression bonding (TCB) for electronics packaging in the field of heterogeneous integration. The technological challenges include the use of an adapted induction coil for homogeneous heat distribution, the implementation of ISM (industrial, scientific, medical) radio band frequencies in the high frequency (HF) and very high frequency (VHF) range up to f0 = 40.68 MHz, and the assembly of a heating system based on an RF generator and automatic matching unit for impedance modulation. Finite element analysis (FEA) was used to calculate the electromagnetic (EM) fields based on the coil design used. The inductive heating was successfully carried out using a generator power of P = 100 W with coil currents in the range of I0 = 10.1 to 11.3 A (amplitudes). With this setup, a peak temperature of Tf_max = 633 °C in the Al frames could be achieved after th = 10 s. This corresponds to an average heating rate of dT/dt = 63.3 K/s.

Hot stamping is an important technology for manufacturing high-strength components. This technology offers the possibility to achieve significant weight reductions. In this study, cushion-ram pulsation (CRP), a new technology for hot stamping on servo-screw presses, was investigated and applied for hot stamping. Compared to a conventional process, the tests yielded a significantly higher drawing depth. In this paper, the CRP technology and the first test results with hot stamping were described in comparison to the conventional process