The Study Of Wear And Corrosion Resistance On Micro Arc Plasma Cladding On The Surface Of Piston Rod

In the process of coal mine safety production,hydraulic support plays an important role in the safety of fully-mechanized working face,and the piston rod is an important part of hydraulic support.This paper mainly studied the wear-resistant and corrosion-resistant strengthening technology of the piston rod surface in the hydraulic support,and used micro-arc plasma cladding technology to obtain the best surface material of the piston rod.The alloy powder of the cladding layer was optimized and the cladding process was optimized.The specific research contents are as follows:The composition of cladding material 1Cr13 Fe-based alloy powder is optimized and the cladding sample is prepared.The microstructure of the cladding sample is observed by scanning electron microscope,the phase composition of the sample is analyzed by X-ray diffractometer,the mechanical properties of the sample are tested by Vickers hardness tester,and the wear resistance and corrosion resistance are carried out.The corrosion properties were tested and the cladding process was optimized.The optimized parameters of coating on piston rod surface are as follows:distance between nozzle and substrate is 9 mm,overlap width is 2 mm,cladding current is 110 A,cladding rate is 200³50 mm/min,plasma flow rate is 1.5².0L/min,powder flow rate is 6⁸ L/min,protective flow rate is 9¹2 L/min,and ion flow rate is 1.5².5 L/min.By using the optimized process parameters,the Fe-based alloy cladding layer with good adhesion,no defect and neat surface was obtained.The hardness and porosity are the main factors affecting the quality of the cladding layer.When the molybdenum,nickel and titanium content ratio is3.5:2.0:1.5,the hardness is the largest,and the porosity is the smallest when the molybdenum content ratio is 3.5:6.0:0.5.When the content of main elements in alloy powder is 0.2%C,12.5%Cr,1.0%B,0.8%Si,3.5%Mo,0.5%Ti and 6.0%Ni,the modification effect is the best.Microstructure observation showed that the microstructure of the cladding layer was mainly composed of hexagonal bovine eye-like phase,bar-like hard phase and matrix structure,and the phase was mainly composed of?Fe,Cr?₇C₃ and?Fe,Cr?₃C carbide eutectic phase and gamma-solid solution.The microstructure and morphology of overlap zone and non-overlap zone are mainly dendrite.The disordered arrangement of dendrite in overlap zone reduces stress concentration and increases wear resistance of alloy cladding layer.Cladding layer of alloy powder with 0.2%C,12.5%Cr,1.0%B,0.8%Si,3.5%Mo,0.5%Ti and 6.0%Ni is superior to substrate 27SiMn in wear resistance and corrosion resistance.Compared with substrate,the microhardness of cladding layer is as high as 1 427 HV,the wear resistance is 3.0 times of matrix,and the corrosion resistance is 6.6 times of matrix.The cladding layer can effectively protect the substrate,improve the comprehensive performance of the hydraulic support's piston rod in the underground,so that it can safely and efficiently underground mining.