Ultrasonic characterization of heat-treatment effects on SAE-1040 and -4340 steels

摘要: Abstract In this work microstructural characterization and mechanical testing results were correlated with ultrasonic velocity sound attenuation of steels SAE-1040 SAE-4340. Both types subjected to three heat treatment; the first was annealing at 850 °C, second austenitizing 1000 °C followed by oil quenching third similar then water quenching. Treatments steel resulted in microstructures containing different ferrite pearlite contents, inter-lamellar spacing also grain size. Similar content obtained when SAE-4340 whereas, into martensite. With SAE-1040, reduced order annealing–oil–water due reduction on expense pearlite. The same change phases from comparison pearlite, martensite possessed higher crystal lattice distortion, dislocation density lower elastic modulus all which contribute reducing velocity. Attenuation increased because spacing. gave an opposite extent anisotropy. properties hardness predominantly affected leading logical correlation parameters.