ASTM F1714   髋关节摩擦磨损试验机    Hip wear simulator fatigue Testing Systems  ISO 14242

Significance and Use

3.1 This guide uses a weight-loss method of wear determination for the polymeric components used with hip joint prostheses, using serum or demonstrated equivalent fluid for lubrication, and running under a dynamic load profile representative of the human hip-joint forces during walking (1,2).⁵ The basis for this weight-loss method for wear measurement was originally developed (3) for pin-on-disk wear studies (see Practice F732) and has been extended to total hip replacements(4,5) femoral-tibial knee prostheses (6), and to femoropatellar knee prostheses (6,7).

3.2 While wear results in a change in the physical dimensions of the specimen, it is distinct from dimensional changes due to creep or plastic deformation, in that wear generally results in the removal of material in the form of polymeric debris particles, causing a loss in weight of the specimen.

3.3 This guide for measuring wear of the polymeric component is suitable for various simulator devices. These techniques can be used with metal, ceramic, carbon, polymeric, and composite counter faces bearing against a polymeric material (for example, polyethylene, polyacetal, and so forth). This weight-loss method, therefore, has universal application for wear studies of total hip replacements that feature polymeric bearings. This weight-loss method has not been validated for high-density material bearing systems, such as metal-metal, carbon-carbon, or ceramic-ceramic. Progressive wear of such rigid bearing combinations generally has been monitored using a linear, variable-displacement transducers or by other profilometric techniques.

1. Scope

1.1 This guide describes a laboratory method using a weight-loss technique for evaluating the wear properties of materials or devices, or both, which are being considered for use as bearing surfaces of human-hip-joint replacement prostheses. The hip prostheses are evaluated in a device intended to simulate the tribological conditions encountered in the human hip joint, for example, use of a fluid such as bovine serum, or equivalent pseudosynovial fluid shown to simulate similar wear mechanisms and debris generation as found in vivo, and test frequencies of 1 Hz or less.

1.2 Since the hip simulator method permits the use of actual implant designs, materials, and physiological load/motion combinations, it can represent a more physiological simulation than basic wear-screening tests, such as pin-on-disk (see Practice F732) or ring-on-disk (see ISO 6474).

1.3 It is the intent of this guide to rank the combination of implant designs and materials with regard to material wear-rates, under simulated physiological conditions. It must be recognized, however, that there are many possible variations in the in vivo conditions, a single laboratory simulation with a fixed set of parameters may not be universally representative.

1.4 The reference materials for the comparative evaluation of candidate materials, new devices, or components, or a combination thereof, shall be the wear rate of extruded or compression-molded, ultra-high molecular weight (UHMW) polyethylene (see Specification F648) bearing against standard counter faces [stainless steel (see Specification F138); cobalt-chromium-molybdenum alloy (see Specification F75); thermomechanically processed cobalt chrome (see Specification F799); alumina ceramic (see Specification F603)], having typical prosthetic quality, surface finish, and geometry similar to those with established clinical history. These reference materials will be tested under the same wear conditions as the candidate materials.

1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

3.1本指南使用磨损测定一个减重方法用于髋关节假体的聚合物成分，使用血清或证实等效流体的润滑，运行下的动态负载配置文件代表人体髋关节的力量在行走过程中（1 2）.5磨损测量这种减重方法的基础是最初的开发（3）磁盘上的针磨损研究（见实践F732），并一直延伸到全髋关节置换（4,5）股胫骨的膝关节假体（6），femoropatellar膝关节假体（6,7）。

3.2当磨损导致试样的物理尺寸的变化，这是明显的尺寸变化由于蠕变或塑性变形，穿一般的查询结果中去除材料的形式的聚合物碎片颗粒，造成损失的试件重量。

3.3本指南是适用于各种仿真器的设备，用于测量聚合物组分的磨损。这些技术可以使用金属，陶瓷，碳，聚合物，复合计数器面靠紧的聚合材料（例如，聚乙烯，聚缩醛，等等）。这种减肥方法，因此，全髋关节置换，具有聚合物轴承磨损研究具有普遍的应用。此减肥方法并没有得到证实高密度材料的轴承系统，如金属 - 金属，碳 - 碳或陶瓷 - 陶瓷。一般已逐步磨损等刚性轴承组合使用线性可变位移传感器或其它轮廓仪技术监测。

1。范围

1.1本指南介绍了使用一个减重技术评估磨损性能的材料或设备，或两者兼而有之，目前正在考虑使用人体髋关节置换假体的轴承表面的实验室方法。髋关节假体的评价为了模拟中遇到的人的髋关节的摩擦磨损条件的设备，例如，如牛血清，或相当于pseudosynovial的流体的流体中使用，以模拟在体内发现的相似的磨损机理和碎片产生的，测试频率为1赫兹或更低。

1.2自髋模拟器方法允许使用实际植入物的设计，材料，和生理负荷/动作组合，它可以代表一个更符合生理模拟比基本筛选磨损测试，如磁盘上的针（见实践F732）或磁盘上的环（见ISO 6474）。

1.3本指南的目的是模拟生理条件下材料的磨损率方面，植入物的设计和材料的排列组合。然而，必须认识到，有许多可能的变化中的一个单一的实验室模拟体内条件，可能并不普遍代表性的一组固定的参数。

1.4参考材料的候选材料，新的设备，或部件，或它们的组合进行比较评价，其应是挤压或压缩成形，超高分子量（UHMW）聚乙烯（见规格F648）轴承的磨损率对标准计数器的面孔[不锈钢（见规格F138）;钴铬钼合金（见规格F75）;钴铬合金热机械处理（见规格F799）;氧化铝陶瓷（见规格F603）]，具有典型的假体质量，表面完成后，那些既定的临床病史几何相似。这些参考材料将被测试相同的磨损条件下，作为候选材料。

2. Referenced Documents (purchase separately) 

ASTM Standards

D883 Terminology Relating to Plastics

G40 Terminology Relating to Wear and Erosion

ISO Standard

ISO6474 

二、产品特点:         

无需油源的直线电机技术，保证洁净的测试环境

轴向通道采用Can总线式控制方式

高速直线作动器

独特的驱动器轴承系统，确保由于样品和夹具的偏移或是有侧向力情况下，加载链仍处于对中状态

适用于各种材料和元器件的动静态测试

高动态性能，频率最大可达50 Hz

±10000N 最大动态轴向载荷

光学编码器用于精确的数字位移控制，及对试样的变形控制。

单相电源驱动，无需额外液压油源、冷却水、气动空气

基于业内先进控制方式的数字控制器

高刚度、精确对准的双立柱加载框架与位于横梁上的驱动器

Dcell 先进载荷传感器技术，实现更快测试，减少惯性差

灵活多样的T型台底座，适用于装配各种规则/不规则的夹具和样品

仪器设计紧凑简洁 – 机架占地面积不到0.5 m²  

三、主要技术参数

最大试验力：±1000N;

试验力示值精度：2%-100%FS范围内，各点均为小于±1.0%;

试验力动态示值波动度：0.5%FS;

作动器最大位移：±50mm;示值精度±0.5%FS;

主要试验波形：正弦波、方波、三角波、斜波等。

试验频率：0.01-10Hz;

四．设备配置：微机伺服动静态疲劳测试系统主要组成部分：

1．横梁电动调整装置，

2．进口伺服作动缸、日本松下驱动装置；

3．数据采集控制系统：动静态伺服控制器和中文软件系统

4．美国进口动态专用力传感器