Heat Treatment Programs And Process Optimization On Wear Resistant Products Of High Chromium Cast Iron

High chromium white cast iron have excellent wear resistance performance has beenwidely used and played irreplaceable role in modern industrial equipment industries,Meanwhile, provides a huge market share for casting factory. However, although Chinahas decades history in high chromium cast iron production,but some enterprisesengaged in high chromium cast iron casting productions still have confusion incomposition adjustment and production process, Facing the low index performanceproductions or the technical bottleneck in quality problem can not be solved, evencaused customer and economic losses situations.This paper on the basis of a foundrymanufacturers traditional process, as the manufacturers product of containing17%Crand containing26%Cr high chromium cast iron wear-resistant for objects, Startingfrom the theory of destabilization treatment and sub-critical treatment, Study andsummary the rules of different heat treatment methods and parameters on highchromium cast iron performance. According to different content Cr of high chromiumcast iron heat treatment process put forward new understanding and the existing fuzzyunderstanding in the past has been clarified. Furthermore, This work used of rules andtheory solved the practical problems for manufacturers.In this paper, the main results asfollows:1.As Cr17high chromium white cast iron large flat plate for objects,explored thepossibility of required hardness through sub-critical treatment and the rules ofrequirement for as-cast matrix sub-critical treatment and heat treatment processparameters. The results showed that under the condition of as-cast matrix was mainlyfor pearlite, sub-critical treatment cannot be effectively improve the parts hardness. Byincrease Mn element and reduce Si element conten.The as-cast matrix given prioritywith the austenitic, Under the condition of optimized process parameters,subcriticaltreatment can improve the hardness of the high chromium cast iron and improve thewear resistance of products.2.Researches show that destabilization treatment failed to get the required hardnessproducts,Subcritical treatment can be used as a rescue measures to improve its hardnessto a certain extent,Using this method, manufacturers effectively improve the hardness ofunqualified products and saved a large number of unqualified products in successfully,saved the huge economic loss for the enterprise.3.Through the analysis all kinds of phase diagram in domestic and foreign literature,Based on experiments and production practice, The author puts forward a new cognition that the effect of destabilization temperature on high chromium cast iron, Namelycontaining Cr in different range the effect of austenitizing temperature was opposite;For Cr20~28%high chromium cast iron, Moderately improve the austenitizingtemperature can be reduce the carbon content in austenite, can obviously improve theproduct final hardness due to reducing austenitic stability; For Cr <20%of the highchromium cast iron appropriately reduce the austenitizing temperature,helped reduce thestability of austenite and conducive to improve the hardness. This cognition,successfully solved the two types of components and more products processingtechnical problem for the enterprise.4.Explore the new heating method of high chromium cast iron destabilizationtreatment in austenitizing stage, Compared with the traditional process,Useingappropriate high or low temperature austenitizing treatment, not only effectively obtainthe required hardness, but also improved the toughness of the products.For the rules of specific material microstructures and properties of high chromiumcast iron in effect of different specific heat treatment methods and parameters, thisarticle also from the theory was discussed.