The Research On Corrosion Resistant Of Ni-Cr-Mo-Mx Alloy

As one of three kinds of failure modes of the mechanical components, corrosion of metals connects with all regions of economy directly. Therefore, based on the referencing to nowadays advance corrosion resistant alloys, six schemes versatile Ni-Cr-Mo-Mx corrosion resistant alloys were designed and prepared by manual electro- arc furnaces in this thesis. Alloys were solution-treated at 1140℃for 2.5h. Corrosion resistance and mechanisms of these alloys were researched through erosion, electrochemical corrosion and high temperature oxidation.Erosion test of alloys was performed in the solutions of sulphuric acid, hydrochloric acid, mixtural acid (10%HCl +10%HNO₃) and 6% FeCl₃. The results show that the alloy as the corrosion rate of increase of hydrochloride acid concentrations increased 60 percent of the most corrosive sulfuric acid.The anodic polarization curves in different electrolyte solutions were measured by the experiments of electrochemical corrosion. The actions of all elements in alloy were analyzed by discovering the changes of corrosion potentials, corrosion current density, passivation potentials , passivation retaining current density and slope of Tafel reciprocal in different of alloys and in different electrolyte solutions.The results show that the sulphuric acid content of 3% Cu alloy corrosion resistance of the strongest. In hydrochloric acid, corrosion resistance of the alloy with the increase in Cu weakened. Ti-resistant alloys will enhance the oxidation of the medium in corrosion resistance, resistance weakened alloy reduction of medium pitting corrosion resistance and the ability, Fe-resistant alloys will reduce oxidation and reduction of medium ability to corrosion, will increase alloy pitting resistance Capacity.Adopted by weight at 800℃on the Ni-Cr-Mo-Mx alloy of high-temperature oxidation performance.The results show that the alloy of weight gain logarithm with the law. Cu alloy will reduce high-temperature oxidation performance, Ti alloy high temperature oxidation will improve performance.