| Title |
Research Paper - Transformations - : Effect of Austenizing Treatment Condition on Microstructures and Mechanical Properties of HY180 Steels |
| Authors |
남태현(Tae Hyun Nam); 조규봉(Gyu Bong Cho); 허경철(Gyeong Chul Hur); 안인섭(In Shup Ahn) |
| Abstract |
Effect of grain size and inclusions on tensile strength and the Charpy V-notch impact absorption energy of HY180 steels has been investigated by means of optical microscopy, energy dispersive X-ray spectrometry, scanning electron microscopy, tensile tests and Charpy V-notch impact tests. Grain growth during austenizing treatments in Ti-modified alloy was smaller than that in Ti-unmodified alloy. and consequently Ti addition was very effective to grain refinements of HY180 steels. Inclusions containing Ti and S were formed in Ti-modified alloy, while MnS in Ti-unmodified alloy. Tensile strength decreased with raising austenizing temperature, which was attributed to the grain growth. The Charpy V-notch impact absoprtion energy of Ti-unmodified alloy increased with rasing austenizing temperature, while it kept almost constant in Ti-modified alloy, although grain size of the alloy increased. |