Tirta Andy, Prasetyo Yus, Baek Eung-Ryul, Choi Chul-Jin
Department of Materials Science and Engineering, Yeungnam University, Gyeongsangbuk-Do 712-749, Republic of Korea.
J Nanosci Nanotechnol. 2011 Jan;11(1):249-55. doi: 10.1166/jnn.2011.3284.
Micropart fabrication via 17-4 PH stainless nanopowder injection molding was investigated. The nanopowder was mixed with a binder that was based on wax to produce a feedstock composed of 45% powder and binder (the powder load). Initially, the fit and proper test was done before the micropart was made by making some bars of green samples, which the properties were examined after the sintering process. The examination involved the mechanical properties such as the porosity, hardness, and some of metallurgical aspects, such as the second-phase formation and the final compound after the sintering. The results showed that utilizing 17-4 PH stainless nanopowder is promising for micropart fabrication since it can form a nearly full-density sintered sample with a low porosity and good toughness, and can provide a smooth surface finish. After this, the investigations followed with the injection of the feedstock into the PDMS micromold that was formed by the nickel pattern from the X-Ray LIGA process. The green samples successfully produced a high-aspect-ratio sample with a thickness of up to 1 mm and an aspect ratio of 15 in the microchannel part. Then the green samples were sintered at 1,300 degrees C for 2 h, since from the initial test, they showed optimum parameters with nearly full density, low porosity, and a high degree of hardness. The research shows the excellent results of the application of the 17-4 PH stainless nanopowder to micropart fabrication.
研究了通过17-4 PH不锈钢纳米粉末注射成型制造微零件的方法。将纳米粉末与一种基于蜡的粘结剂混合，以制备一种由45%的粉末和粘结剂组成的原料（粉末装载量）。最初，在制造微零件之前，通过制作一些生坯样品棒进行了适配性和适当性测试，在烧结过程后对其性能进行了检查。检查涉及机械性能，如孔隙率、硬度，以及一些冶金方面，如第二相形成和烧结后的最终化合物。结果表明，使用17-4 PH不锈钢纳米粉末对于微零件制造是有前景的，因为它可以形成一个具有低孔隙率和良好韧性的近全密度烧结样品，并能提供光滑的表面光洁度。在此之后，研究接着将原料注射到由X射线LIGA工艺的镍图案形成的PDMS微模具中。生坯样品成功地在微通道部分制造出了一个高纵横比的样品，其厚度高达1毫米，纵横比为15。然后将生坯样品在1300摄氏度下烧结2小时，因为从最初的测试来看，它们显示出了具有近全密度、低孔隙率和高硬度的最佳参数。该研究表明了17-4 PH不锈钢纳米粉末在微零件制造中的应用取得了优异成果。
