Hip arthroplasty or total hip arthroplasty involves removing the diseased hip joint and replacing it with an artificial joint called a hip prosthesis/hip joint implant.
Hip implants include:
An acetabular (acetabular cup/acetabular shell) with inserts or liners made of plastic, ceramic or metal
a spherical piece (femoral head) made of metal or ceramic
A metal handle (femoral stem) made of titanium or cobalt/chromium based alloy (in some designs, the femoral stem and femoral ball are integrated; other designs are modular for additional customization)
Hip implants are typically made of cobalt-chromium alloy (eg ASTM F1537), titanium alloy (eg Ti6Al4V ELI) or medical grade stainless steel (316LVM).
Fixing is a challenge
Small batch production
Some forged and cast blanks for the stem
Bar material for the femoral head and acetabular cup
Typical machines for this part include multi-axis machines, 3-axis lathes, 5-axis VMCs, and multi-tasking machines (such as the Mazak Intergrex E410e).
The inner spherical arc ramping is an efficient and safe machining with the advantage of obtaining a high quality surface with longer tool life, lower tool breakage possibilities and shorter machining times. It is best to use a positive rake cutter.
Advantages when machining the outer spherical surface include longer tool life and safe machining.
Lateral femoral head processing enables high quality surfaces and longer tool life through a safe process. It is best to use a positive rake angled insert.
The processing of the conical hole of the femoral head is an effective process for processing flat bottoms.