钢中铌的沉淀析出具有沉淀强化和晶粒细化的作用。
And the precipitation of Nb has the effect of precipitation hardening and grain refinement.
研究发现，钛含量增加，使钢中获得细小沉淀物的弥散分布，细化晶粒，增强时效硬化，从而提高该钢的抗拉强度。
The results showed that as the content of Ti increasing , fine precipitates distribute dipersely, grain fine and age - hardening enhanced in the steel, so tensile strength in this steel is improved.
方法：应用共沉淀法制备纳米羟基磷灰石/壳聚糖复合材料，并采用TEM、SEM、XRD等手段对材料晶相组成、微观结构、晶粒大小进行分析表征。
Methods:Nano-hydroxyapatite/chitosan composites were prepared through a co-precipitation method. The properties of these composites were characterized by means of TEM , SEM, XRD test machine.
应用推荐