第一，从均质材料向复合材料发展。以前人们只使用金属材料、高分子材料等均质材料，现在开始越来越多地使用诸如把金属材料和高分子材料结合在一起的复合材料。第二，由结构材料为主向功能材料、多功能材料并重的方向发展。以前讲材料，实际上都是指结构材料。但随着高技术的? First, from homogenous materials to composite materials. In the past, people only used homogeneous materials such as metal materials and polymer materials, and now they are increasingly using such composites as metal materials and polymer materials. Second, from structural materials to functional materials, multi-functional materials both in the direction of development. Before speaking materials, in fact, refers to the structural materials. But with high-tech?