Processing of ultra-high molecular weight polyethylene by hot isostatic pressing, and the effect of processing parameters on its microstructure

2004 ◽  
Vol 44 (10) ◽  
pp. 1848-1857 ◽  
Author(s):  
Rizwan M. Gul ◽  
Frederick J. McGarry
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Hot Isostatic Pressing ◽  
Processing Parameters ◽  
Isostatic Pressing ◽  
Ultra High Molecular Weight

Using Isostatic Pressing Techniques to Mold Uhmwpe

1995 ◽  
Vol 394 ◽  
Author(s):  
Joel Higgins ◽  
David Schroeder
Keyword(s):  
Molecular Weight ◽  
Quality Control ◽  
High Molecular Weight ◽  
Bearing Material ◽  
Isostatic Pressing ◽  
Manufacturing Methods ◽  
Particulate Debris ◽  
And Performance ◽  
Ultra High Molecular Weight

Ultra High Molecular Weight Polyethylene (UHMWPE) has been and is currently the standard for bearing material used in the orthopedic industry. The components are produced using a variety of manufacturing methods, many of which can have an effect on the longevity and performance of the device. Recently there has been extensive research into the causes of loosening of orthopedic devices. One area that has been targeted as a cause for loosening is reactions to particulate debris from the bearing surfaces of these appliances. As biological reactions to particulate become better understood, there has been an increased emphasis on the quality of the UHMWPE forms used for orthopedic bearing surfaces. Due to this increased awareness, various manufacturing and quality control improvements have been made throughout the industry.

Application of ultra-high molecular weight polyethylene in a hydraulic drive

2020 ◽  
pp. 77-78
Keyword(s):  
Molecular Weight ◽  
Low Temperature ◽  
High Molecular Weight ◽  
Hydraulic Drive ◽  
Control Valve ◽  
Hydraulic Control ◽  
Hydraulic Motor ◽  
Hydraulic Pump ◽  
Hydraulic Oil ◽  
Ultra High Molecular Weight

The use of ultra-high molecular weight polyethylene (UHMW PE) for the manufacture of various parts, in particular cuffs for hydraulic drives, is proposed. The properties and advantages of UHMW PE in comparison with other polyethylene materials are considered. Keywords ultra-high molecular weight polyethylene, hydraulic pump, hydraulic motor, hydraulic control valve, hydraulic oil, low temperature. [email protected]

scholarly journals Structure, processing and performance of ultra-high molecular weight polyethylene (IUPAC Technical Report). Part 4: sporadic fatigue crack propagation

2020 ◽  
Vol 92 (9) ◽  
pp. 1521-1536
Author(s):  
Clive Bucknall ◽  
Volker Altstädt ◽  
Dietmar Auhl ◽  
Paul Buckley ◽  
Dirk Dijkstra ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Fatigue Crack ◽  
Crack Propagation ◽  
High Molecular Weight ◽  
Fatigue Crack Propagation ◽  
Crack Tip ◽  
Individual Growth ◽  
Paris Equation ◽  
Number Of Cycles ◽  
Ultra High Molecular Weight

AbstractFatigue tests were carried out on compression mouldings supplied by a leading polymer manufacturer. They were made from three batches of ultra-high molecular weight polyethylene (UHMWPE) with weight-average relative molar masses, ${\overline{M}}_{\mathrm{W}}$, of about 0.6 × 106, 5 × 106 and 9 × 106. In 10 mm thick compact tension specimens, crack propagation was so erratic that it was impossible to follow standard procedure, where crack-tip stress intensity amplitude, ΔK, is raised incrementally, and the resulting crack propagation rate, da/dN, increases, following the Paris equation, where a is crack length and N is number of cycles. Instead, most of the tests were conducted at fixed high values of ΔK. Typically, da/dN then started at a high level, but decreased irregularly during the test. Micrographs of fracture surfaces showed that crack propagation was sporadic in these specimens. In one test, at ΔK = 2.3 MPa m0.5, there were crack-arrest marks at intervals Δa of about 2 μm, while the number of cycles between individual growth steps increased from 1 to more than 1000 and the fracture surface showed increasing evidence of plastic deformation. It is concluded that sporadic crack propagation was caused by energy-dissipating crazing, which was initiated close to the crack tip under plane strain conditions in mouldings that were not fully consolidated. By contrast, fatigue crack propagation in 4 mm thick specimens followed the Paris equation approximately. The results from all four reports on this project are reviewed, and the possibility of using fatigue testing as a quality assurance procedure for melt-processed UHMWPE is discussed.

Sign in / Sign up

Export Citation Format

Share Document