Nickel alloy welding is a class of alloys with high strength and a specific antioxidant and corrosion resistance at 650~1000℃. It is subdivided into nickel-based heat-resistant alloys, nickel-based corrosion-resistant alloys, nickel-based wear-resistant alloys, nickel-based precision alloys, and nickel-based shape memory alloys according to its main properties. High temperature alloys are divided into iron-based high temperature alloys, nickel-based high temperature alloys, and cobalt-based high temperature alloys according to the different substrates. The nickel-based high-temperature alloy is abbreviated as a nickel-based alloy.
The main alloying elements of nickel-based wear-resistant alloys are chromium, molybdenum, and tungsten, and contain small amounts of niobium, tantalum, and indium. In addition to its wear resistance, it has excellent oxidation resistance, corrosion resistance, and welding properties. It can be manufactured as a wear-resistant component or as a cladding material, which can be wrapped over other substrate materials by the process of overlay welding and painting. Nickel-based alloy powders are available as self-fusing alloy powders and non-self-fusing alloy powders.
Non-self-melting nickel-based powders are nickel-based alloy powders that do not contain B, Si, or have low B, Si content. This type of powder is widely used in plasma arc spray coating, flame spray coating, and plasma surface reinforcement. Mainly include Ni-Cr alloy powder, Ni-Cr-Mo alloy powder, Ni-Cr-Fe alloy powder, Ni-Cu alloy powder, Ni-P, and Ni-Cr-P alloy powder, Ni-Cr-Mo-Fe alloy powder, Ni-Cr-Mo-Si high wear-resistant alloy powder, Ni-Cr-Fe-Al alloy powder, Ni-Cr-Fe-Al-B-Si alloy powder, Ni-Cr-Si alloy powder, Ni-Cr-W-based wear-resistant and corrosion-resistant alloy powder, etc.
The nickel-based self-melting alloy powder is formed by adding the right amount of B and Si to the nickel alloy powder. The so-called self-fusing alloy powder is also known as a low eutectic alloy; a hard-sided fusion is a series of powder materials formed by adding alloying elements (mainly Boron and silicon) with low melting point eutectic in nickel, cobalt, iron-based alloy. Commonly used nickel-based self-fusing alloy powders include Ni-B-Si alloy powder, Ni-Cr-B-Si alloy powder, Ni-Cr-B-Si-Mo, Ni-Cr-B-Si-Mo-Cu, high molybdenum nickel-based self-fusing alloy powder, high chromium-molybdenum nickel-based self-fusing alloy powder, Ni-Cr-W-C-based self-fusing alloy powder, high copper self-fusing alloy powder, tungsten carbide dispersion type nickel-based self-fusing alloy powder, etc.
Role of the elements in the alloy.
1, Boron, silicon element: significantly reduce the alloy melting point, expand the solid-liquid phase line temperature zone, and form low-melting co-crystal, deoxidation, and slagging function; the hardening of the coating, strengthening; improve the operation process performance.
2. The role of copper elements: improve the corrosion resistance to non-oxidizing acids.
3, The role of chromium elements: substantial solution strengthening, passivation, improve corrosion resistance, and high-temperature oxidation resistance; rich in chromium and carbon, Boron natural to form chromium carbide, chromium boride hard phase to improve alloy hardness and wear resistance.
4, The role of molybdenum elements: sizeable atomic radius, reliable solution after the lattice distortion, significantly strengthen the alloy matrix, improve the substrate’s high-temperature strength, and red-hardness; can cut off, reduce the coating in the reticulation; improve cavitation resistance, erosion ability.