Research On Alumina Ceramics Metallization And Its Composite With High Chromium Cast Iron

With the continuous promotion of industrial demand and technological development,industrial wear-resistant materials have gradually developed from the initial high manganese steel and low alloy wear-resistant cast steel materials to high chromium cast iron materials.Elevated chromium cast iron has good wear resistance,excellent toughness and strength,good resistance to high-temperature and corrosion,and low production cost,making it the preferred material for wear-resistant structural components.However,pure metal wear-resistant material cannot balance superior wear resistance and impact resistance.In view of the high hardness and high wear resistance of ceramic materials,the preparation of ceramic metal composite materials by composite metal wear-resistant materials and ceramics has important research significance,and was also a research hotspot in the field of wear-resistant materials.Ceramics belong to inorganic non-metallic materials and have significant differences from metallic materials in terms of crystal types and physical chemistry.The vast majority of metal cannot be wet ceramics,and ceramics and metals cannot be directly connected together.Therefore,solving the wettability problem of metal on ceramic surfaces was of utmost importance in the preparation of ceramic/metal composite materials.At present,the commonly used and most effective method was to coat the surface of the ceramic with a layer of metal,that was,ceramic metallization.This article used chemical copper plating method and molybdenum manganese method to metallize the surface of Al₂O₃ceramics.Mechanized Al₂O₃ceramics and high chromium cast iron were prepared into ceramic/metal composite materials using a high-temperature atmosphere furnace,and the ceramic metallization and ceramic/metal composite materials were studied.For the metallization of chemical plating method,the influence of the ratio of chemical plating solution on the morphology and phase of the metal layer was investigated.Through EDS testing of the cross-section of Al₂O₃ceramic/metal composite material,the optimal formula for chemical copper plating was determined to be formaldehyde 10 g/L,copper sulfate 7.5 g/L,sodium hydroxide20 g/L,sodium potassium tartrate 39.5 g/L,EDTA-2Na 52 g/L,and potassium ferrocyanide 0.07 g/L.The p H value was 12,the reaction temperature was 50℃,and the plating time was 60 min.For the metallization of molybdenum manganese method,The composition of metallization paste was studied,and metal oxides were used as activators to promote metallization sintering.Sintered in an oxidizing atmosphere and reduced at low temperature.The effects of metallization temperature and metal oxides on metallization were investigated.XRD testing was conducted on the mechanized layer to study its composition.By conducting SEM and EDS tests on metabolize ceramics,the morphology of the mineralized layer and the migration of elements during the metallization process were analyzed.And by conducting metallographic and SEM tests on the cross-section of Al₂O₃ceramic/metal composite materials,the optimal molybdenum manganese method metallization formula was determined to be Mo O₃（60 wt%）,Mn O₂（20wt%）,Ni O（10wt%）,Co₂O₃（10wt%）,with a metallization temperature of 1250℃and insulation for 60 min;The reduction temperature was700℃,the insulation was 60 min.,and the reduction atmosphere was a mixture of nitrogen and hydrogen gas（nitrogen 95%,hydrogen 5%）.The wear resistance of ceramic/metal composite materials was tested using a ball mill.The test results showed that the wear resistance of ceramic/metal composite materials prepared by the two methods of metallization was higher than that of a distinct high chromium cast iron under the same test conditions,which was increased by 20%（chemical copper plating metallization）and 50%（molybdenum manganese metallization）,respectively.