Microhardness tester for metals at elevated temperatures

Abstract

An apparatus h as been devised for measuring t h e hardness of electrodeposite d coatings at te mperatures up to 900 0 C in an in er t at mosphere. Coatings t h ick er t han about 0 .07 millimeter (0.003 in ch) may be tested. The main parts of t he apparatus are: (1) Thc i ndenting mechanism, co nsisting of a Vicker's diamond mo un ted on a shaft of fused silica ; (2) a mcchani cal devi ce for raisin g and lowe rin g t h e indenter; (3) a micrometer device for o ri e nt in g t he sp ecimen unde r the indenter ; (4) t he heating unit. The force on t h e indenter is varied either by dead-weight loading or by changing t h e gas pressure inside of t he appa-rat us. Some typical m eas ureme nts m ade with the a ppa ratus a re given.