ASTM F1714-96 (R2018) pdf free download.Standard Guide for Gravimetric Wear Assessment of Prosthetic Hip Designs in Simulator Devices.
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 vñ’o. 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 he recogniied, 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 Istainless steel (see Specification F138): cobalt- chromium-molybdenum alloy (see Specification F75): thermomechanically pr(xessed cobalt chrome (see Specification F799); alumina ceramic (see Specification F603)I, having typical prosthetic quality, surface finish, and geometry similar to those with established clinical history. These reference maerials will be tested under the same wear conditions as the candidate materials.
3. 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). The basis for this weight-loss method for wear measurement was originally developed (3) thr pin-on-disk wear studies (see Practice F732) and has been extended to total hip replacements (4,5) fenioral-tihial 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.ASTM F1714 pdf download.