Microstructure, mechanical properties and wear behavior of metallic, nonmetallic and deep cryogenically chilled ASTM A216 WCB steel

• Published in: Journal of alloys and compounds Vol. 506; no. 2; pp. 645 - 652
• Main Author: Hemanth, Joel
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 17.09.2010; Elsevier
• Subjects: Chilled; Chilling; Chills; Chromium; Chromium steels; Condensed matter: structure, mechanical and thermal properties; Cooling; Deformation and plasticity (including yield, ductility, and superplasticity); Exact sciences and technology; Heat capacity; Mechanical and acoustical properties; Mechanical and acoustical properties of condensed matter; Mechanical properties; Mechanical properties of solids; Metallography; Microstructure; Physical properties of thin films, nonelectronic; Physics; Steels; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thermal properties of condensed matter; Thermal properties of crystalline solids; Tribology and hardness; Mechanical properties; Heat capacity; Metallography; Microstructure; Metallic conduction; Mechanical strength; Carbon steels; Chromium additions; Hardness; Specific heat; Casting; Wear; Chromium; Wear resistance; Tribology
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2010.07.036

▶ Microstructure of the chilled steels is finer than that of the un-chilled steel with random orientation of carbide particles in pearlite matrix. ▶ Strength, hardness and wear resistance of the chilled steels are superior to those of the un-chilled steel. It was found that these properties increase with an increase in carbide particles in fine pearlite matrix. ▶ At lower load, chilled steels exhibited mild wear regime with high coefficient of friction and at higher loads they exhibited severe wear with better wear resistance than the un-chilled steel. ▶ Size of the wear debris decreases because of rapid crack propagation of a brittle body under compression where as the size of the carbide fragmentation remain approximately the same. ▶ Rate of chilling is identified as an important parameter that affects microstructure and mechanical behavior of WCB steel. This paper deals with the production of Deep Cryogenically Chilled (DCC) ASTM A216 WCB steel (plane carbon group) having 0.5% chromium, subject to different chilling rates to study the effect of chilling on microstructure and mechanical properties. In this investigation, metallic, nonmetallic and subzero chills (one each) were used. The specimens taken from casting were tested for their strength, hardness and wear behavior. Results of the investigation reveal that chilling rate and addition of chromium (0.5%) has improved both mechanical properties (strength and hardness) and wear resistance of the steel developed. Out of all the chills, subzero chill is found to be good in improving mechanical properties because of its high volumetric heat capacity (VHC). It is concluded from the above investigation that type of chill and chilling rate has an effect on mechanical properties.