Effect Of Alloying And RE Modification On Microstructure And Properties Of HCCIs

High chromium white cast iron has good wear resistance and has been widely applied in various fields.In recent years,in order to meet the needs of industrial development,researchers have introduced a large number of new theories to introduce high chromium white cast iron,and its microstructure and properties have also been greatly improved,and the plasticity and toughness are still an important factor restricting the application of high chromium white casting.This study by alloying and modification of different content of Hypoeutectic?Cr25 and Cr27?and hypereutectic high chromium cast iron?Cr45?treatment,the microstructure characteristics of scanning electron microscope,VHX 600 microscope,EDS,X-ray diffraction and surface properties of X CFT-1 type of material tester to observe and analyze the samples,the detection of different modifier and nickel titanium content on high chromium cast iron impact toughness,hardness and erosion resistance.The mechanism of action is analyzed and the better content is determined.The results of the study are as follows:1.RE-Mg on the microstructure,improve the hypoeutectic high chromium cast iron purification liquid metal has obvious effect of modifier amount in 0.6%when the impact toughness reaches the maximum value of 5.7J/cm²;adding modifier after the hardness increased after the first drop,in 0.6%when the maximum is HRC51.14.The effect of RE-Mg on the metamorphism of Hypereutectic white cast iron is weak.The modifier has little effect on the primary crystal,and it mainly improves the morphology of eutectic carbides.The impact toughness of the hypereutectic white cast iron is improved,and the hardness of the alloy is not obviously improved by adding RE-Mg.2.Nickel alloying can increase the density of the matrix and increase the density with the increase of nickel content.The nickel content was 0.9%,and the hardness of Hypereutectic High Chromium White Cast Iron and hypereutectic high chromium white cast iron reached the maximum at the same time.Titanium is a dispersed TiC in high chromium white cast iron,and its hardness is higher than that of M₇C₃.Therefore,the tissue shows high hardness and wear resistance.As an external nucleation,TiC increases the nucleation rate and refines the carbides in the tissue.Especially in hypereutectic,the formation of a large amount of titanium carbide makes the microstructure change to the hypoeutectic,and has a certain influence on the impact toughness of the material.