M42高速钢粉末级配规律和注射成形工艺参数优化

研究了M42高速钢粉末的粒度级配对粉末振实密度的影响规律，并采用正交试验法研究了注射温度、注射压力、注射流量、保压压力及其交互作用对注射坯质量的影响．试验结果表明，粗细粉末进行级配能够有效提高粉体的堆积密度．与-400目粉末相比，＋140目与-400目的原料粉末通过级配，振实密度可提高44．3％～56．4％．注射工艺参数正交试验发现注射温度、保压压力及其交互作用对注射坯质量的影响最为显著．试验确定的标准长方体弯曲试样最佳注射工艺参数为：注射温度160℃、注射压力82MPa、注射流量42％及保压压力31MPa．

Investigation of M42 high-speed steel powder's gradation and the influence of injection parameters on its green compact's quality

The influence of particle gradation on tap density of M42 high-speed steel powder was studied and the effect of injection parameters such as injection temperature,pressure, flux as well as holding pressure and their interaction on as-molded compacts density was evaluated by means of orthogonal experiments in order to optimize injection molding process. Experimental results indicated that coarse versus fine powder gradation could effectively improve powders＇s packing density. Compared with the tap density of -400 mesh powders,the tap density of powders consisting of ＋140 mesh particles and --400 mesh particles could be raised by 44. 3% to 56.4% through optimized particle graduation. The results of orthogonal tests revealed that injection temperature, holding pressure and their interaction put the heav- iest influence on a injection molded green compact＇s density. The optimized injection parameters for standard rectangular bending specimens were of injection temperature 160℃,injec tion pressure 82 MPa,injection flux 42% and holding pressure 31 MPa.