In modern industrial processing, almost all mechanical parts are made of metal. The most important problems faced by these parts are surface wear and metal corrosion. The solution to these problems is the thermal spraying technology that we're going to talk about today. Let's talk about the scope of application of thermal spraying technology.

First, wear resistance - the largest application area of thermal spraying technology at high temperature and low temperature. These coatings are specifically classified as follows:

(1) Resistance to adhesive wear or scratches - two surfaces sliding relative to each other, debris from one surface to another surface, the occurrence of adhesive wear or scratches. The special typical coating is cobalt based tungsten carbide, nickel chromium / chromium carbide coating.

(2) Abrasive wear - abrasive wear occurs when the harder surface slides on the softer surface and there is wear between the two surfaces. Abrasive wear occurs when fibers and silk threads pass through the surface at high speed. The typical typical coatings are cobalt based nickel chromium alloy, self melting alloy mixed molybdenum and chromium oxide coating.

(3) Wear resistance to micro-vibration-cyclic stress induced by repeated loading and unloading leads to surface cracking and large-area shedding. The special typical coating is alumina / titanium dioxide coating.

(4) corrosion resistance wear - liquid flow produces mechanical shock on the surface. The special typical coating is aluminum bronze coating.

(5) erosion wear resistance occurs when particles carrying gas or liquid are impacting on the surface at high speed. The typical coating is alumina / titanium dioxide and alumina coating.

Two. High temperature resistance and oxidation resistance. These coatings resist chemical or physical decomposition and improve the high-temperature properties of parts. This type of thermal spray is divided into the following:

(1) thermal barrier coating, which acts as a thermal barrier between parts and high temperature environment. The typical coating is zirconia coating stabilized by yttrium oxide.

(2) high temperature oxidation resistant coating protects the substrate against high temperature oxidation. The typical coating is nickel / chromium coating.

(3) heat resistant corrosion coating to protect the matrix exposed to hot corrosive gases. The typical coating is nickel / chromium coating.

That's part of the scope of thermal spraying, and we'll leave a few parts to talk about next time.