One client who responses Foxconn product has very high requirement for the flatness,oxydic color and machining deformation. We advice the 7075 T651 material.At the earlier stage, he chose the imported material 7075 T651 from our factory and several other suppliers to process and compare, found that our flatness was the best.But the material after post processing changed to be soft and color did not keep consistent. We studied client’s post processing:he wanted to improve processing speed, so that the material was more sufficient to remove internal stress. The material was put into high temperature oven for 3-4 hours before processing, leading to the hardness of the material become soft, changed the material inside molecular structure, so the color was not consistent and hardness changed soft. We suggested client to cancel the pyroprocess and control feed rate.The product finally achieved satisfactory result.。