MKT 3401 Chapter : MKTG5 IE Ch02 PPT
Document Summary
Properties of selected materials after various heat treatments (high carbon steel, about 1 in. thick) Coarse pearlite with free or fe3c along g. b. Martensite on surface, bainite or pearlite in core. Bainite (feathery b at higher temperatures below knee, and acicular. Tempered martensite/ usually fine acicular fe3c/ ferrite matrix. 60; tough temperature, longer time yield lower hardness) Martensite in case, p or b in core. Very slow cooling in furnace, about 2-12 hrs. Quenching to an intermediate temp. equilibrating (about 1 hr) then cooling to r. t. by any method. 600-1200 f (for 12 hr 5 min. ) cooling to r. t. by any method. M8, holding for 5-10 min, then quenching in cold water (to avoid quench cracks) Cr, <0. 5%fe: annealing (stress relieving) (any material) Solution treating in single phase region at around 950 f (4-12 hr), quenching in cold water (w-condition), then aging. T4- w+ natural age hardening at r. t. to full hardness.
