Simultaneous Acquirement of High Complication and functionality by New Metal Injection Molding Process.

MIM工艺有望成为高密度、高性能、复杂零件近净成形的一种先进粉末加工技术。然而，由于使用模具，仍然存在MIM紧凑的形状和体积限制的问题。本研究尝试将无磁性奥氏体不锈钢（SUS304L、316L）、马氏体不锈钢（SUS420J1）等相同或不同的材料与高磁通密度的纯铁相结合，通过对溶剂脱蜡过程中析出的蜡进行MIM薄空心件的过程连接，生产出更大、更复杂的功能性零件，作为改进MIM工艺中上述问题的新途径之一。所得结果如下：1)通过MIM过程连接（在溶剂脱粘过程中使用脱出的蜡形成绿色压块），获得了相同材料（SUS304L/SUS304L、SUS420J1/SUS420J1）与不同材料（SUS304L/SUS420J1）的完美连接对。2)对于铁与不锈钢压坯对，由于收缩起始温度不同，连接困难。采用细粒度不锈钢粉进行真空烧结，获得了良好的连接效果。3)对于奥氏体不锈钢和硅铁致密体的结合，获得了高功能性（磁性非磁性&（1.60特斯拉））和完美的结合。

MIM process is hoped to be an advanced powder processing technique for near net shape forming the high density, high performance, and complicated pars. However, there still remains the issue of limitation in the shape and volume of MIM compacts because of using the die.In this study, as one of new approaches to improve the above problems in MIM process, MIM in-process joining of thin and hollow parts ***ing the exuded wax during solvent debinding step has been attempted to produce larger, more complicated and functional parts by combination of the same or different materials such as non-magnetic austenitic stainless steels (SUS304L, 316L) and martensitic stainless steel (SUS420J1) and pure iron with high magnetic flux density. Results obtained were as follows ;1) Perfect joined couples of the same (SUS304L/SUS304L, SUS420J1/SUS420J1) and different (SUS304L/SUS420J1) materials were obtained by MIM in-process joining (application of the exuded wax form green compacts during solvent debinding step).2) For the couple of iron and stainless steel compact, joining was difficult because of the different starting temperature of shrinkage. However, excellent joining was obtained by using stainless steel powder with fine particle size and vacuum sintering.3) For the couple of austenitic stainless steel and ferro-silicom compact, high functionality (magnetic non-magnetic ＆ (1.60 Tesla)) and perfect joint were obtained.