生物医用二级纯钛注射成形研究

Research on Powder Injection Molding of Grade 2 CP-Titanium for Biomedical Application

随着医疗产品市场对生物医用材料需求量的不断增加,比强度高、弹性模量低、耐腐蚀,生物相容性好的钛和钛合金受到人们越来越多的关注。相对于传统的机加工和模压加工工艺,金属粉末注射成形能够实现产品的低成本、大批量近净成形,有效的提高材料利用率,扩大了钛和钛合金的应用范围。本文利用水溶性注射料体系和商用球形钛粉制备了注射料,并进行了力学性能试样的制备,通过优化烧结工艺参数,制得烧结试样的物理力学性能如下:氧含量0.228%,氮含量0.015%,屈服强度443 MPa,极限拉伸强度554MPa,延伸率20.9%,相对密度96.9%。试样整体性能满足ASTM F2989-13外科植入用金属注射成形纯钛部件标准。

With the increasing demand for biomedical materials, titanium and titanium alloys are becoming increasingly attractive because of their high specific strength, low elastic modulus, good corrosion resistance and fantastic bio-compatibility. Compared with traditional machining and mold processing technology, MIM appears to be ideal for the processing of titanium parts （ even highly complex structures）, as typical advantages are high material utilization and low production costs in large-quantity manufacturing. In this study, water soluble binder and commercial spherical titanium powder were employed for the injection molding of the mechanics performance samples. Through the sintering parameters optimization, samples with relative density of 96.9% , oxygen content of 0. 228% , nitrogen content of 0. 015% , yield strength of 403 MPa and plastic elongation of 20. 9% were obtained. These properties （except the relative density） meet the requirements of ASTM F2989-13 for grade 2 pure titanium.