Effect of Cu and Sn on Hot Stamping Formability of Aluminum Silicon Coating

The conventional aluminum-silicon coating products are easy to form cracks and have poor formability during hot stamping. The influence of different Cu and Sn contents on the hot stamping properties of aluminum silicon coating was studied by adding Cu and Sn to the aluminum silicon coating. Samples of aluminum silicon coating steel plates with different Cu and Sn contents were obtained by hot-dip simulation test machine. The coating structure of aluminum silicon coated steel samples with different Cu and Sn contents was studied by means of inductively coupled plasma spectrometer, scanning electron microscope and energy spectrum analyzer. Hot stamping was carried out by means of resistance heating furnace and U type stamping machine. The crack propagation of aluminum-silicon coating was studied by scanning electron microscope,energy spectrum analyzer and glow spectrometer. The results show that when a certain amount of Cu is added to the aluminum-silicon coating, a small amount of Cu-rich phase is formed in the coating, and a certain amount of added Sn makes the structure smaller and more uniform; the hardness of the Al-Si-Cu coating increases after heating and the formability of the coating are deteriorated. But the addition of a certain amount of Sn can improve the hot stamping formability of the aluminum silicon coating.