The corrosion testing of the taper connection according to ASTM F1875 can be performed using two different methods:

Method 1:
The taper connection of the hip replacement is subjected to at least 10 million load cycles in a test chamber filled with electrolyte (0.9% NaCl) following ASTM F1140. The isolated fluid is chemically analyzed for particles and ions. Afterwards, the components of the taper connection are examined microscopically and with an electron microscope. Additionally, weight loss can be measured as an indicator of wear. This method quantitatively measures particles and ions and qualitatively assesses surface damage of the taper due to micromotion and corrosion.

Method 2:
The hip replacement is placed in a test chamber filled with electrolyte solution (0.9% NaCl), so that the electrolyte covers the taper and part of the stem. The contact surfaces are isolated from the electrolyte. The taper connection is loaded as in Method 1 according to ASTM F1140, but forces and test frequency may be lower.

• Procedure A:
  A calomel electrode is used as a reference for measuring the corrosion potential with a voltmeter. The test ends when a stable potential is reached.
• Procedure B:
  A large-area counter electrode is placed in the solution to simulate the stem surface. An ammeter is connected between the hip replacement and the counter electrode. The difference in current before and during loading serves as a measure of wear corrosion between the taper and ball of the hip replacement.