中文摘要：

针对选区激光烧结金属零件致密度低、机械性能差等问题,分析了金属粉末选区激光烧结的工艺特点,讨论了扫描路径对金属粉末烧结成形的影响以及金属粉末直接烧结成形的基本机理.选用镍基F105Fe粉末进行选区激光烧结成形金属零件,采用扫描电镜、显微硬度测量、阿基米德定律等方法,研究了扫描路径对选区激光烧结制件微观组织、显微硬度和致密度的影响.结果表明,扫描路径的不同不会改变制件的微观组织,但对组织的均匀化和细化有一定的影响;扫描路径对制件的机械性能影响显著,变向扫描制备的制件显微硬度比较高,致密性最好,短边同向扫描制备的制件显微硬度最高.

英文摘要：

In order to solve the problems of lower relative density and bad mechanical property of metal parts manufactured by Selective Laser Sintering（SLS）,the characteristics of the selective laser sintering were analyzed briefly first,then the effect of the scan path upon metal forming was discussed in detail,and finally the mechanism of the laser sintering metallic powders was explored preliminarily.Ni-based F105Fe alloy powders parts were manufactured via SLS.According to scanning electron microscope（SEM）,micro-hardness testing machine and archimedes law etc,the influence of scanning path on microstructure,micro-hardness and relative density of SLS samples were analyzed.The results show that different scanning paths have no influence on microstructure but will affect the homogenization and refinement especially for mechanical property.The parts which manufactured by scanning path with direction shift have high hardness and greatest relative density while the parts manufactured by scanning path with the same direction have the best micro-hardness.