改善金属注射成形制作17-4PH直齿轮厚度方向的失真度  

Improving the thickness direction deviation of 17-4PH spur gear made by metal-powder injection molding

作　　者：李杰 叶德全 邱耀弘 LI Jie;YE Dequan;QIU Yaohong(Vigor Precision Hardware and Plastic Products Co.,Ltd.,Dongguan 523000,China;You Need Enterprise Consulting Co.,Ltd.,Kunshan 215300,China)

机构地区：[1]东莞域嘉精密五金塑胶制品有限公司,广东东莞0523000 [2]昆山耀德企业咨询有限公司,江苏昆山215300

出　　处：《粉末冶金工业》2022年第6期64-69,共6页Powder Metallurgy Industry

摘　　要：金属粉末注射成形(Metal-powder Injection Molding,以下简称MIM)以小型金属零件且带有复杂形状的制品为代表,尤其是质量低于50 g以内的铁系合金,在我国和全球已经是非常普遍的技术,不过以MIM工艺制作精密齿轮仍有一定的难度,因为齿轮是一种具有重复性特征且要求很高的零件,尝试采用当今MIM界最常使用的沉淀硬化型不锈钢17-4PH制作直齿轮,并观察比较MIM制品与设计模型厚度方向的失真度。经先导实验结果发现MIM烧结后的直齿轮厚度方向失真度为0.07~0.08 mm,在进行模具的修改后并调整MIM的成形参数(注射参数、生坯摆放方式、烧结参数设计)之后,最终直齿轮厚度方向失真度范围改善至0.02~0.03 mm;经对照美国齿轮制造协会(AGMA)标准表后发现,研制的MIM直齿轮的精度等级超过ANSI/AGMA 2000-A88-Q8,到达Q9等级。Metal-powder injection molding(MIM)was an excellent choice for small metal parts with complex shapes.In particular,iron-based alloys with a weight less than 50 g had become a very popular technical option in China and Global.However,it is still difficult to manufacture precision gears with MIM because gears are parts with high repeatability requirements.This paper attempts to use precipitation hardening stainless steel-17-4PH to make spur gears,observe and compare the distortion of MIM products and design models in the thickness direction.17-4PH was the most commonly used in MIM industry.According to the pilot experiment results,the thickness direction distortion of MIM sintered spur gear is found to be 0.07-0.08 mm.After modifying the tooling and adjusting the MIM forming parameters(include injection parameters,green body placement mode,and sintering parameter design),the thickness direction distortion of the spur gear can be improved to 0.02-0.03 mm.After checking the American Gear Manufactures Association(ANSI/AGMA 2000-A88)table,it is found that MIM gear products can reach the Q9 grade.

关 键 词：金属粉末注射成形 直齿轮 沉淀硬化型不锈钢 失真度 

分 类 号：TH132.41[机械工程—机械制造及自动化]