Research On Surface Hardening Technology Of 4145H Stator And Rotor Based On Laser Quenching

In recent years,with the rapid economic development,China's demand for oil and natural gas and other energy sources has gradually increased.The exploration of high temperature and high pressure wells,deep wells and ultra deep wells has increased significantly.The complex and harsh drilling environment is particularly prominent.Since the nitrile rubber stator in conventional screw drilling tools is difficult to meet the performance requirements of high temperature resistance,it is necessary to prepare all-metal screw motors.All metal stator and rotor bear various complex alternating stresses such as high-speed rotation,friction,large torque and impact force.It is prone to corrosion,fracture and severe wear.The development and application of geological drilling technology and equipment are facing severe challenges.Faced with the technical difficulties of the mechanical wear characteristics of the surface of the all metal stator and rotor,this paper discusses the technical characteristics and research status of laser heat treatment,and proposes a process research plan for laser heat treatment technology.In this paper,4145H steel for rotor and stator has been laser quenched by HJ series high power transverse flow CO₂laser.Through metallographic analysis,hardness test and friction and wear experiment,the influence mechanism of laser process parameters on quenching quality was studied.The three-dimensional solid model was established by ANSYS software,and the temperature field simulation of the laser quenching process was realized.In this paper,through the comprehensive analysis of the experimental results and simulation results under different laser process parameters,it is concluded that the laser process parameters have a significant impact on the quenching quality.With the increase of laser power and laser scanning speed,the content of martensite structure,surface hardness and surface wear show a trend of increasing first and then decreasing.The phase change cooling rate decreases with the increase of laser power and increases with the increase of laser scanning speed.The results show that the laser power and scanning speed should be controlled in a reasonable range if the best effect of laser quenching and transformation hardening is obtained:the laser spot diameter is 10mm,the laser power is about 2kW,the laser scanning speed is about400mm/min,at this time,the laser radiation temperature is about 1550°C,and the corresponding cooling rate is about 800°C/s.Finally,uniform fine and dense martensite grains will be generated on the surface of the material.This paper focuses on the feasibility of laser heat treatment of all metal stator and rotor steel process parameters.It provides theoretical basis and experimental basis for laser heat treatment technology to improve material properties of 4145H steel for stator and rotor.Expand the application range of laser heat treatment technology,and guide the processing and production of drilling tools.It is of great practical significance to promote the development and application of geological drilling technology and equipment.