Study On Process Of RE-boronizing For Q235 Steel And Boride Layer Anti-corosion Property In Aluminum Melt

To improve the anti-corrosion property of carbon steel Q235 and cast iron RTCr2 in melt-Aluminum with boride was the purpose of this paper..The method of multi-boronizing was used to improve the structure and properties of boride layer The elements of multi-boronizing were Rare Earth element and Boron element. The method of orthogonal experiment was used to investigate the effeet of parameter of boronizing proeess on the thiekness of the boride layer. The parameter of boronizing Proeess included boronizing temperature, Boronizing time, the addition of boron source and the addition of Rare Earth. Then the proper parameters of boronizing Proeess were determined. Devices and equipments such as optical microscope, metallographic microscope, scanning electr on microscope (SEM), X-ray diffractometer, microhardness tester and so on, were used to observe the structure of boride layer and test anti-corrosion aluminum property of boride layer.The conclusions as follows:1. The thickness of boriding layer increase with temperature risnig, time prolonging and content of boride source increasing. Boriding temperautre has a Maximum effect on boriding layers thickness, and boriding time has a minimal effect on boriding layers thickness. Rare Earth could accelerate the growth of the boride layer and improve the compactability of boride layer. There was a optical range for the addition of Rare Earth. The rational boronizing process as follows:Boronizing temperature 920℃. Boronizing time 6h. The addition of Rare Earth 3%.2. The anti-corrosion melt aluminum property of Q235 steel and cast iron boronized were better than untreated samples. The anti-corrosion aluminum melt property of Q235 steel and cast iron RE-boronized were better than single boronized samples. The layer of samples RE-boronized was compacter than these of single boronized. The anti-corrosion aluminum melt property of cast iron RE-boronized was best. The anti-corrosion aluminum melt property of Q235 steel is better than RTCr2 cast iron3. The high temperature oxidation resistance of the boride layer was better than thatof Q235 steel. The high temperature oxidation resistanee of the Q235 RE-borided layer compared with these of borided Q235 steel not improve.