DEVELOPMENT OF ELECTROPLATING PROCESSES TO ELIMINATE HYDROGEN EMBRITTLEMENT IN HIGH-STRENGTH STEEL. Period Covered: February 1956 to May 1957

Technical Report · Fri Nov 01 04:00:00 EST 1957

OSTI ID:4306771

Chilton, J E

The embrittlement of cadmium plated high-strength steels e.g., (SAE 4340) by hydrogen is of serious concern to the Air Force. Unexpected failures of highly stressed components have been experienced. It has been found that cadmium plating from a sulfamate, a perchlorate, or a fluoborate bath wdth addition agents can be accomplished without embrittling the steel, but that the quality and adherence of the cadmium plate emerging from these baths as compared with the cadmium plate from a cyanide bath, indicates the need for further evaluation before use. In order to evaluate the effects of various degrees of hydrogen embrittlement on the steel, a sensitive mechanical test method was required. The important criteria were that the test coupon be of such geometry that it could be plated uniformly and that the test would evaluate only the effect of hydrogen embrittlement. Simple bend tests and notched bar tensile tests have been commonly used for studying the embrittling effect. The bend test, torsion test, and static sustained load beam test were investigated. A static sustained load beam test, using a 9- x 1/4- x 1/2-in. specimen with the grain transverse to the length was adopted. The SAE 4340 specimens were heat treated to 280,000 to 300,000 psi tensile strength and the fracture time, under a given stress, was taken as a measure of the degree of hydrogen embrittiement. it was found that replicate specimens show a large deviation in fracture times in spite of the care that was given to the selection preparatlon, and testing techniques. These deviations are due to the normal defects and variables that are present in commercial, air melted, aircraft quality steel. (auth)

• Research Organization: Stanford Research Inst., Menlo Park, Calif.
• NSA Number: NSA-12-007268
• OSTI ID: 4306771
• Report Number(s): WADC-TR-57-514; AD-142316
• Country of Publication: United States
• Language: English

Related Subjects

ADHESION
AIR
AIRCRAFT
BORIDES
BRITTLENESS
CADMIUM
CHLORIDES
CONTROL
CYANIDES
DEFECTS
ELECTROCHEMISTRY
ELECTRODEPOSITION
ELECTROPLATING
FAILURES
FLUORIDES
GRAIN BOUNDARIES
HEAT TREATMENTS
HYDROGEN
MATERIALS TESTING
MECHANICS
MELTING
MINERALOGY, METALLURGY, AND CERAMICS
PLATING
PREPARATION
ROTATION
STEELS
STRESSES
SULFATES
TENSILE PROPERTIES
VARIATIONS