Wear resistance of plasma immersion ion implanted Ti6Al4V
Wear resistance of plasma immersion ion implanted Ti6Al4V
复制标题
DOI：
10.1016/0257-8972(96)02884-8
复制
发表时间：
1996-11-01
影响因子：
5.4
通讯作者：
Collins, GA
中科院分区：
文献类型：
--
作者：
Johns, SM;Bell, T;Collins, GA
为了改善Ti6Al4V合金的摩擦学性能，对Ti6Al4V合金进行了等离子体浸没离子注入(PI3TM)处理。特别是，这项研究是为了将其潜在地应用于骨科植入物的表面工程。近年来，澳大利亚核科学和技术组织(ANSTO)开发了PI3。该技术的混合性质结合了离子注入和离子渗氮的元素，并已被证明可生产具有独特表面特性和最佳性能特性的部件。在350、450和550℃的纯氮气气氛中进行处理，每种情况下，样品都被处理5h，直接施加高压脉冲(通常为40kV)。使用标准的CSEM销-盘磨损试验机，以单晶红宝石球作为接触唇，评估处理样品的耐磨性。用掠角X射线衍射仪(GAXRD)分析了表面改性层中的相组成。然后将这些发现与常规离子注入和低温等离子体氮化样品平行工作所获得的结果进行了比较。结果表明，550℃的高温处理温度是大幅提高Ti6Al4V材料性能所必需的。在这些条件下，PI3技术促进了诺氏硬度的显著提高，耐磨性比传统的离子注入高出一个数量级。与未经处理的Ti6Al4V相比，磨损率通常降低了四个数量级。这被认为与在这种温度下α-钛中氮的流动性增加有关，从而产生了更深、更硬的情况。在此范围内的所有温度下，PI3Ti6Al4V样品的显微组织中都观察到了TiN的存在。
The plasma immersion ion implantation (PI3 TM) process has been employed in the treatment of the Ti6Al4V alloy in order to improve its notoriously poor tribological properties. In particular, this study was undertaken with a view to its potential application for the surface engineering of orthopaedic implants.PI3 has been developed over recent years at the Australian Nuclear Science and Technology Organisation (ANSTO). The hybrid nature of this technique combines elements of both ion implantation and plasma nitriding, and has been shown to produce components with unique surface properties and optimum performance characteristics.A detailed study of the PI3 process on the Ti6Al4V alloy has been undertaken. Treatment was carried out in a pure nitrogen atmosphere at temperatures of 350, 450 and 550 degrees C. In each case, specimens were treated for 5 h, with a high voltage pulse (typically 40 kV) applied directly to the workpiece.Wear resistance of the treated samples was assessed using a standard CSEM pin-on-disc wear machine, with a single crystal ruby ball as the contact lip. Glancing angle X-ray diffraction (GAXRD) was employed to determine the phases present in the surface modified layer. These findings were then compared to those achieved from parallel work with conventionally ion implanted and low temperature plasma nitrided samples.It was established that a high treatment temperature of 550 degrees C was necessary for substantial improvements in the properties of the Ti6Al4V material. Under these conditions the PI3 technique promoted significant increases in Knoop hardness, and wear resistance an order of magnitude greater than conventional ion implantation. Wear rates were typically reduced by four orders of magnitude compared to those of the untreated Ti6Al4V. This is thought to be associated with the increased mobility of nitrogen in alpha-Ti at these temperatures, producing a deeper, hardened case. The presence of TiN was observed in the microstructure of PI3 Ti6Al4V samples at all temperatures in the range.