Assertion: detector's contact | /r/MadeOf | hardened steel point
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Source sentences:
text: Invented in 1906 by Henry H. C. Dunwoody, this consisted of a piece of silicon carbide (SiC, then known by the trade name carborundum), either clamped between two flat metal contacts, or mounted in fusible alloy in a metal cup with a contact consisting of a hardened steel point pressed firmly against it with a spring.