什么叫金属的超塑性? 用金属试样做拉伸实验,在常态下一般延伸率(δ)不过百分之几十,就是在高温状态下,也很少超过百分之一百。但很早就有人发现,某种锌-铝合金和铋-锡合金在极慢速拉伸时,可以得到近2000％的延伸率。这一现象引起了人们的注意。人们首先想到:这种特大的延伸率,其它材料是否也具备呢?并且每种材料出现大延伸率的条件又是什么呢?有没有共同的规律 What is the superplasticity of metal? Tensile test with a metal specimen, in the normal state of general elongation (δ) but dozens of percent, that is, at high temperatures rarely exceed one hundred percent. It has long been found, however, that a certain zinc-aluminum alloy and bismuth-tin alloy can achieve an elongation of nearly 2000% at very slow stretching. This phenomenon has aroused people’s attention. The first thing people think about is this extra-large elongation, are other materials also available, and what are the conditions for the large elongation of each material? Are there any common rules