Laser cladding powder for 30CrMnSiNi2A steel and preparation method

Abstract

The invention relates to laser cladding powder for 30CrMnSiNi2A steel and a preparation method. The laser cladding powder is prepared from the following components in weight percent: 0.8% to 1.0% of Cr, 0.75% to 1.10% of Mn, 0.65% to 1.10% of Si, 2.0% to 3.2% of Ni, 0.16% to 0.22% of C, 0.15% to 0.20% of Cu, 0.015% to 0.020% of P, 0.01% to 0.015% of S, 0.001% to 0.015% of rare earth and the balance of Fe. The invention further provides the preparation method of the laser cladding powder, the laser cladding powder is exclusively used in a laser cladding technique of the 30CrMnSiNi2A steel, excellent bonding strength and low metallurgical defects and dilution rate of a cladding interface are guaranteed, the toughness of a cladding layer is increased, the wettability of the cladding powder is improved, the cracking of the cladding layer is inhibited, and the crack growth rate is reduced.

Description

technical field [0001] The invention relates to laser cladding technology, in particular to laser cladding powder for 30CrMnSiNi2A steel and a preparation method thereof. Background technique [0002] 30CrMnSiNi 2 Because of its high strength, good plasticity, toughness and hardenability, as well as good fatigue and wear resistance, super-strength steel is widely used in aviation important forgings, sheet metal parts and weldments, such as machine Wing girders, connecting bolts, landing gear and other stressed components. 30CrMnSiNi 2 The tensile strength of A super strong steel (σ b ) up to 1600 ~ 1800MPa, fracture toughness (K Ic ) can reach 105MPa / m, cooled in oil, and the hardenable section diameter can reach more than 50mm. However, the high-frequency vibration of the aircraft under service conditions is likely to cause fatigue failure of parts, and most of the cracks originate from the surface of the workpiece, which is quite harmful; in addition, 30CrMnSiNi2A is ...

AI Technical Summary

Problems solved by technology

The implementation of many existing cladding processes mostly uses thermal spray powder as the raw material. The main problem is that the laser energy density is higher, which leads to serious burning of the components during the cladding process and insufficient powder fluidity.

There are few research reports on laser cladding powder for 30CrMnSiNi2A super-strength steel matrix. Because the tensile strength is as high as 1600-1800MPa, and the elongation after fracture is maintained at about 10%, it is difficult to use laser cladding. The difficulty is that it is difficult to guarantee The laser cladding layer achieves the same or close strength and toughness match with the parent body

In the prior art, Co50, Ni60, GH4169, AF1410, Fe90 and other existing thermal spraying powders are used to clad and repair the 30CrMnSiNi2A super-strength steel matrix, which is difficult to achieve good results

The main quality defects are high dilution rate of the cladding layer, high porosity of the cladding layer, more poor fusion at the interface of the cladding layer, oxidation inclusions and microcracks, and serious oxidation of the cladding layer, etc.

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