Effect of Heat Treatment Parameters on the Characteristics of Thin Wall Austempered Ductile Iron Casting

International Conference on Recent Advances in Materials, Mechanical and Civil Engineering

材料科学;机械制造;土木建筑工程

Upadhyaya, Rajat^1 ; Singh, K.K.^1 ; Kumar, Rajeev^2

Department of Foundry Technology, National Institute of Foundry and Forge Technology (NIFFT), Ranchi

834003, India^1

Department of Mechanical Engineering, Birla Institute of Technology (BIT), Ranchi

835215, India^2

关键词: Austempered ductile irons;    Austempering temperature;    Effect of heat treatments;    Ferrite-pearlite;    Plate thickness;    Structure change;    Treatment process;    Ultimate tensile strength;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/330/1/012084/pdf
DOI  :  10.1088/1757-899X/330/1/012084

来源: IOP

【 摘 要 】

The technology of thin parts is necessary steps to designers for energy consuming equipment to choose accurate material based on material properties. Here austempering treatment process was utilized to acquire thin wall austempered ductile iron castings. The plate thickness (2-5) mm were austenitized at 900 °C for, 30 minutes took after by holding at 350°C, 400°C and 450°C inoculated by Ce-Ca-Al-S-O-FeSi,Zr-Mn-Ca-Al-Ba-FeSi and Sr-Al-Ca-FeSi at 0.2wt%,0.4wt% and 0.6wt% for 2,5 and 10 minutes for every temperature.The austempered samples are comparatively harder than the as-cast ductile iron plates. The micro hardness(HV20) also decreases with increase in austempering temperature for a given austempering time for thinner plates and also the micro hardness(HV20) is more for the samples treated at 350°C than those treated at 400°C and 450°C at 0.4wt% for a given austempering time. The yield strength and ultimate tensile strength of 2 mm thin wall austempered ductile iron are higher and ductility and impact strength are lower than that of as-cast 2 mm thin plate ductile iron inoculated by Ce-Ca-Al-S-O-FeSi compare to Zr-Mn-Ca-Al-Ba-FeSi and Sr-Al-Ca-FeSi at 0.4wt%. This may be attributed to the change in the structure change from ferrite-pearlite to austenite-bainite.