The invention relates to a method for carrying out
high velocity oxy-fuel spraying on the surface of a roller of a
lithium battery
pole piece rolling
machine. The method of adding
hydrogen into fuel and decreasing the
diameter of a
combustion chamber is adopted. By means of adding the
hydrogen, the heat
enthalpy value and the speed of the
flame are increased. By means of adding of the
hydrogen,
tungsten carbide particles can be reduced and protected, and burning losses and
decarburization are avoided. To further increase the speed of the
flame, the
diameter of an outlet of the
combustion chamber is decreased by 2 mm-5 mm, the pressure of the
combustion chamber is increased, and the speed of the
flame is further increased. Due to adding of the hydrogen, burning losses and
decarburization of the
tungsten carbide particles can be reduced, the heat
enthalpy value of the flame is increased, the
tungsten carbide particles are heated more evenly, a
coating can have higher tenacity and compactness, and the
binding force of the
coating is improved. By means of the method, the speed of the flame is increased, and the aim of increasing the particle spraying speed is achieved; and
tungsten carbide particles at a higher speed
impact on a base body, the
binding force of the
coating and the base body is improved, the inner
binding force of the coating is increased by means of subsequent higher-speed particle
impact, and therefore the binding force of the whole coating is increased.