Study the Microstructure and Mechanical Properties of High Chromium White Cast Iron (HCWCI) under Different Martempering Quenching Mediums

Abstract

The aim of this study is to find an alternative quenching medium for the ordinary nitrate mixture that is cheaper and more available in Iraqi markets. So to obtain the suitable medium , the effect of different quenching mediums used in martempering treatment on the microstructure and mechanical properties of high chromium white cast iron was studied . This type of cast iron is used in mining ,crushing and cement plants as mill liners so it is subjected to extreme conditions of wear and impact that eventually cause failure . In this study, two types of quenching mediums were used in martempering treatment: (50% Sodium hydroxide + 50 % potassium hydroxide) mixture and (50% Sodium nitrate + 50 % potassium nitrate) mixture with different quenching intervals. It is also found that both of the quenching mediums produce higher hardness values at 350°C martempering temperature for 4 hr quenching time ,but there were several advantages and disadvantages associated with using these two different mediums

Keywords

• hardness
• high chromium white cast iron
• martempering
• microstructure
• quenching mediums