In vitro Wear Rate and Co Ion Release of Compositionally and Structurally Graded CoCrMo-Ti6Al4V Structures

Stanley Dittrick; Vamsi Krishna Balla; Susmita Bose; Amit Bandyopadhyay

doi:10.1016/j.msec.2010.07.009

Back

In vitro Wear Rate and Co Ion Release of Compositionally and Structurally Graded CoCrMo-Ti6Al4V Structures

Journal article

Open access

In vitro Wear Rate and Co Ion Release of Compositionally and Structurally Graded CoCrMo-Ti6Al4V Structures

Stanley Dittrick, Vamsi Krishna Balla, Susmita Bose and Amit Bandyopadhyay

Materials science & engineering. C, Materials for biological applications, Vol.31(4), pp.809-814

05/10/2011

DOI: https://doi.org/10.1016/j.msec.2010.07.009

Handle:

https://hdl.handle.net/2376/104904

PMCID: PMC3079500

PMID: 21516206

Files and links (1)

url

https://doi.org/10.1016/j.msec.2010.07.009View

Published (Version of record) Open

Abstract

Laser processing

Functional graded materials

In vitro wear

CoCrMo alloy

Co- ion release

Ti6Al4V alloy

Novel, unitized structures with porous Ti6Al4V alloy on one side and compositionally graded, hard CoCrMo alloy surface on the other side have been fabricated using laser engineered net shaping (LENS™) process. Gradient structures with 50%, 70% and 86% CoCrMo alloy on the top surface showed high hardness in the range of 615 and 957 HV. The gradient structures were evaluated for their in vitro wear rate and Co release up to 3000 m of sliding distance. The wear rate of ultrahigh molecular weight polyethylene and 100% CoCrMo alloy substrates found to depend on the hardness and microstructural features of the counter surface rubbing against them. In general, the wear rate of both the substrates increased with a decrease in the CoCrMo alloy concentration on the top surface of gradient pins. However, the wear rate of gradient pins was lower than 100% CoCrMo alloy pins due to their high hardness. Lowest wear rate in the range of 5.07 to 7.99 × 10 −8 mm 3 /Nm was observed for gradient pins having 86% CoCrMo alloy on the top surface. The amount of Co released, in the range of 0.38 and 0.91 ppm, during in vitro wear testing of gradient structures was comparable to that of 100% CoCrMo alloy (0.25 and 0.77 ppm). Present unitized structures with open porosity on one side and hard, wear resistant surface on the other side can minimize the wear-induced osteolysis and aseptic loosening, and eliminate the need for multiple parts with different compositions for load-bearing implants such as total hip prostheses.

Metrics

4 Record Views

Details

Title: In vitro Wear Rate and Co Ion Release of Compositionally and Structurally Graded CoCrMo-Ti6Al4V Structures
Creators: Stanley Dittrick
Vamsi Krishna Balla
Susmita Bose
Amit Bandyopadhyay
Publication Details: Materials science & engineering. C, Materials for biological applications, Vol.31(4), pp.809-814
Academic Unit: Mechanical and Materials Engineering, School of
Identifiers: 99900546622401842
Language: English
Resource Type: Journal article