CN101275227B - High-temperature-resistant iron-base alloy powder for metallic surface hardening by cladding - Google Patents

Abstract

The invention relates to high-temperature resistance iron based alloy powders used in a metal surface cladding strengthening technology. Constituent elements and the weight ratio of the high-temperature resistance iron based alloy powders are separately: the weight ratio of C is 1 to 2; the weight ratio of Si is 1 to 2; the weight ratio of Mo is 4.0 to 4.5; the weight ratio of Cr is 25 to 30; theweight ratio of Ni is 15 to 20; the weight ratio of Mn is 0.5 to 1; the rest is Fe. An excellent performance of the invention on high-temperature resistance aspect is powerfully verified via test data. And the invention has lower manufacturing cost and is the iron based alloy powders of component surface cladding strengthening which is suitable for working high temperature environment.

Description

High temperature resistant iron-based alloy powder for metal surface cladding strengthening process

technical field

The invention belongs to the field of powder metallurgy, in particular to a high-temperature-resistant iron-based alloy powder used in metal surface cladding strengthening technology.

Background technique

At present, metal surface strengthening cladding alloys used at home and abroad mainly include electrode flux type and alloy powder type; according to material composition, they can be divided into iron-based alloys, nickel-based alloys, cobalt-based alloys, copper-based alloys, composite materials, etc. The main characteristics of iron-based alloy powder are good wear resistance at room temperature, impact resistance, rich source of raw materials, and low cost, but the main problems are poor high temperature resistance and corrosion resistance.

Through searching, two relevant patents were found. A patent related to a special iron-based alloy powder for laser cladding (patent number 02154195.7), the weight composition of the alloy powder is (%): C0.15～0.25; Cr14～17; Ni2～5; Mo1～2; Nb0.25～0.5; Ta0.1～0.4; N0.2～0.4; Si1.1～1.4; B0.1～1.0; the rest is Fe. Another patent relates to a production process of iron-based alloy powder metallurgy products. The weight composition of the alloy powder is (%): Fe95.35; Cu1.5; C0.5; Mn0.4; Mo0.5; Cr1. 5; S0.15; engine oil 0.1. The high temperature resistance and corrosion resistance of the above two patents are very general.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art and provide a high temperature resistant iron-based alloy powder with good performance, low cost and suitable for surface cladding strengthening of parts working in a relatively high temperature environment.

The technical scheme that the present invention solves technical problem is:

A high-temperature-resistant iron-based alloy powder used in a metal surface cladding strengthening process, the constituent elements and their weight percentages are:

C 1～2; Si 1～2; Mo 4.0～4.5; Cr 25～30;

Ni 15~20; Mn 0.5~1; the balance is Fe.

And, the optimal weight ratio of each element is:

C 1.7; Si 1.45; Mo 4.2; Cr 27;

Ni 17; Mn 0.7; Fe 47.95.

Moreover, the alloy powder is prepared by an atomization method, and the hardness of the powder particles is 490-540HV, and the hardness of the cladding layer is 38-42HRC.

Advantage and positive effect of the present invention are:

Through the test data, it is effectively verified that the invention has excellent performance in high temperature resistance, and the manufacturing cost is relatively low, and it is an iron-based alloy powder material suitable for surface cladding strengthening of parts working in a high temperature environment.

Description of drawings

Fig. 1 is a powder morphology picture of the present invention;

Fig. 2 is XRD analysis collection of illustrative plates of the present invention;

Fig. 3 is the microhardness distribution curve of the plasma cladding layer of the present invention;

Fig. 4 is the microstructure picture of plasma cladding layer of the present invention;

Fig. 5 is the cladding layer hardness curve after the high temperature treatment of the present invention;

Fig. 6 is a graph showing the high temperature oxidation performance of the present invention.

Detailed ways

The present invention will be further described in detail below through the specific examples, the following examples are only descriptive, not restrictive, and cannot limit the protection scope of the present invention with this.

A high-temperature-resistant iron-based alloy powder used in a metal surface cladding strengthening process, the constituent elements and their weight percentages are:

C 1～2; Si 1～2; Mo 4.0～4.5; Cr 25～30; Ni 15～20; Mn 0.5～1; the balance is Fe.

The most preferred embodiment of the present invention is (percentage by weight):

C 1.7; Si 1.45; Mo 4.2; Cr 27; Ni 17; Mn 0.7; Fe 47.95.

The invention adopts an atomization method to prepare high-temperature-resistant iron-based alloy powder, and the hardness of the powder particles is 490-540HV.

The advanced nature of the present invention is further verified below by various performance test results.

Figure 2 is the XRD analysis spectrum of the alloy powder. The analysis shows that the phase in the powder is mainly composed of γ (Fe, Cr, Ni) solid solution matrix and (Cr, Fe) ₇ C ₃ .

Figure 3 shows the microhardness curves of the plasma cladding layer of this powder along different layer depths, and the thickness of the cladding layer is 2.6mm.

Fig. 4 is the microstructure of the plasma cladding layer of the present invention, the cladding layer presents an obvious dendrite structure, and the dendrites are relatively small. In the microstructure picture, the white one is a dendritic matrix, and the eutectic structure is distributed among them. Moreover, the XRD analysis results show that the structure of the cladding layer is mainly composed of γ (Fe, Cr, Ni) solid solution matrix and (Cr, Fe) ₇ C ₃ .

Fig. 5 is a curve diagram of treatment temperature and cladding layer hardness. The test method is: take an alloy powder cladding sample with a hardness of 38HRC, put the sample into a box-type resistance furnace for heating. Set the temperature at 400°C, 450°C, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C respectively, keep warm, take out the sample and air cool to room temperature, and measure the hardness of the cladding layer. and take its average. From the curve, it can be seen that compared with the cladding layer without high temperature treatment, when the heating temperature is lower than 750°C, the hardness remains basically unchanged after high temperature treatment, but when the temperature is higher than 750°C, the hardness value begins to decrease.

Figure 6 is a graph showing the high temperature oxidation performance. The test method is: put the alloy cladding layer sample with a thickness of 2mm and a diameter of 18mm into a box-type resistance furnace after treatment and weighing. , heated for 120 hours in total, and the high temperature oxidation degree of the material is characterized by the weight gain. It can be seen from Figure 6 that after the oxidation test at 800°C for 120 hours, the material has no obvious weight gain.

Claims (2)

1. high-temperature-resistant iron-base alloy powder that is used for metallic surface hardening by cladding is characterized in that: it constitutes element and weight percent is respectively:

C 1.7；Si?1.45；Mo?4.2；Cr 27；

Ni 17；Mn 0.7；?Fe?47.95。

2. the high-temperature-resistant iron-base alloy powder that is used for metallic surface hardening by cladding according to claim 1 is characterized in that: adopt the atomization preparation, and its powder particle hardness is 490-540HV.

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