Thomas G. Digges, 81, who retired in 1961 as chief of the thermal metallurgy section of the Bureau of Standards, died of cancer Monday at Sibley Memorial Hospital.

Mr. Digges, a metallurgical engineer, joined the bureau around 1919. He worked primarily on the development of high-Speed steel tools and did research on the strengths and properties of structural steels. He was the author of a number of research and technical papers in his field. He had received both the silver and gold medals of the Department of Commerce for his work.

He was born in Warrenton, Va., and attended the Virginia Polytechnic Institute at Blacksburg until the outbreak of World War I, when he quit college to enlist in the Army.

He moved to the Washington area after the war and attended George Washington University. After graduating with a degree in physics he joined the Bureau of Standards, where he spent 42 years.

Mr. Diggs, who lived in Arlington, was a chairman of the Washington Chapter of the American Society for Metals.

Survivors include his wife, Dorothy Hottel Digges, of the home; two sons, Thomas G. Jr., of Los Angeles, and Robert H., of Mclean, and eight grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Sloan-Kettering Cancer Center, P. O. Box 8918, Church Street Station, New York, N. Y., 10049.