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Home About AAT&D AAT&D Four-Ball Test Machine 4-Ball Test Description (PDF) Testing Services FAQs Contact Us |
AAT&D Four-Ball Friction-and-Wear TesterAnn Arbor Testing & Development, Inc., has developed an improved design for the four-ball friction-and-wear tester (U.S. Patent Number 6,857,306). For details, click the links below. |
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