Effect of cooling rate on the microstructure and properties of FeCrVC

• Published in: Journal of alloys and compounds 2015-06, Vol.634, p.200-207
• Main Authors: Bleckmann, M., Gleinig, J., Hufenbach, J., Wendrock, H., Giebeler, L., Zeisig, J., Diekmann, U., Eckert, J., Kühn, U.
• Format: Article
• Language: English
• Subjects: Alloys; Cooling; Cooling rate; Differential scanning calorimetry; Liquidus; Mechanical properties; Metals and alloys; Microstructure; Phase transitions; Solidification; Thermal analysis; Thermodynamic modeling
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2015.02.004

•Effect of cooling rate on microstructure and microhardness of newly developed steel.•Intensive study of DSC measurements was done including different cooling rates.•Examinations by XRD, EDS and EBSD as well as microhardness on the DSC samples.•Matrix phase changes with cooling rates from ferrit to martensite.•Thermodynamic calculations of solidification process shows good agreement. In this work a systematic investigation of the influence of the cooling rate on the microstructure and properties of a newly developed Fe92.7Cr4.2V2.1C1 (FeCrVC) tool steel is presented. By applying a tailored casting process and sufficiently high cooling rates excellent mechanical properties are obtained for the presented alloy already in the as-cast state. Since no subsequent heat treatment is required, the cooling parameters applied during the casting process play a key role with respect to the evolving microstructure and resulting properties. In the present publication the effect of the cooling rate on the microstructure and properties of as-solidified FeCrVC was investigated. By using differential scanning calorimetry (DSC), several samples were heated up and cooled with continuous rates of 3–50K/min. The received DSC data was used to investigate the alloy’s solidification and phase transformation behavior. Subsequently, these samples were studied regarding their properties and microstructure by different analysis methods (EDX/WDX, EBSD, XRD). With increasing cooling rates the liquidus and solidus temperature are lowered, whereas the solidification interval is enlarged. A higher cooling rate is accompanied by a lower solidification time which results in a refinement of the dendritic microstructure. Furthermore, with rising cooling rates the microhardness increased. This provides the opportunity to make predictions from the applied cooling parameters upon the hardness and vice versa and enables one to draw first conclusions on the mechanical properties of the FeCrVC alloy.