Micro-FAST成形过程中电流大小对颗粒变形的影响

创新性地采用多物理场活化烧结微成形技术(Micro-FAST)制备了316L不锈钢和纯Cu微型齿轮。探讨了电流大小对316L不锈钢和纯Cu粉末体系在烧结过程中颗粒变形的影响。结果表明,在电场、力场和温度场的耦合作用下,升温过程是粉末体系实现致密化的主要过程。由于电塑性效应的影响,粉末体系在致密化过程中表现出的显著特征之一是颗粒的塑性变形。电流越大,颗粒的变形量越大,粉末体系的轴向尺寸减小量越多,最终微型烧结体的相对密度也越大。

Effect of Electric Current Magnitude on Particles Deformation during the Densification Process of Micro-FAST

A novel micro multi-physic fields coupling method (Micro-FAST) was developed for the fabrication of micro gears with 316L stainless steel powders and pure copper powders. The effect of electric current magnitude on the particle deformation in sintering process of 316L stainless steel and pure copper systems was studied. It is shown that the calefactive period plays a key role for densification of powder system with the coupling of electric field, force field and temperature field. A notable feature of the densification process is plastic deformation of particles due to electroplastic effect. With the increasing of electric current, the deformation amount of particles is bigger which results in the increase of axial reduction, consequently improving the densification of samples