JPS6046171B2 - Nickel-based alloy with improved hot workability - Google Patents

Description

Detailed Description of the Invention The present invention aims to improve the strength, corrosion resistance, and magnetic properties inherent to the alloy by minimizing the amount of sulfur and aluminum as impurity elements contained in commercially available nickel-based alloys, as well as silicon. This is a nickel-based alloy with improved hot workability without any loss.

Among the nickel-based alloys, for example, Inconel 60 is used for heating furnace parts, heat exchangers, and turbine parts, while Monel 40 is used for heating furnace parts, heat exchangers, and turbine parts.
PC permalloy alloy is used as a high magnetic permeability alloy for the head core of magnetic recording devices. In addition to the above, target alloys of the present invention include 70% Ni-based electric heating alloy, Bathalloy R-235 heat-resistant alloy, Monel corrosion-resistant alloy, 78% Ni permalloy magnetic alloy, Inconel 601 heat-resistant alloy, Bathalloy corrosion-resistant alloy, and Inconel 63. These include Fuchi heat-resistant alloy, Unitemp C3 heat-resistant alloy, jVAR-M200 heat-resistant alloy, IN-102 heat-resistant alloy, RA-33 side heat-resistant alloy, and Bath Alloy B heat-resistant alloy.

These nickel-based alloys, especially nickel-based alloys containing 60% or more of Ni, have a drawback of low manufacturing yields due to poor hot workability such as hot forgeability and hot rolling properties.

In order to improve the hot workability of nickel-based alloys, for example, there is a method of reducing the amount of sulfur as an impurity element, but this is not economical using current refining technology.

Addition of a sulfide stabilizing element such as magnesium is also effective in improving hot workability, but this is not preferred since it may impair other properties. Therefore, in order to investigate the influence of the impurity elements on the hot workability of various nickel-based alloys, test pieces shown in Figure 1 were prepared and hot-rolled at 1,300°C. The limit rolling rate, which is an index value of workability, was measured.

As a result, as shown in Figure 2, S
It has been found that if the amount of Si is reduced to 0.002% or less, the limit rolling rate can be increased to 50% or more even though the Si content is 0.06% or more and the Al content is 0.005% or more.

However, this requires careful selection of melting raw materials and careful melting and refining, which is unfavorable from an economic standpoint. On the other hand, in the same figure, the limit J rolling ratio at S■0.003 to 0.008% is divided into two depending on the high and low Si level, and
It is high for the material, but it is low for the material i. In other words, it has been found that when Si and N are reduced to 0.05% or less and 0.004% or less, respectively, at 0.003 to 0.008% of S1, a critical rolling reduction of 40% or more can be ensured. Furthermore, regulating the S level to 0.008% or less is not so difficult using current refining technology, and is easier than regulating the S level to 0.002% or less. Based on these findings, the composition of the alloy of the present invention is a nickel-based alloy containing 60% or more of Ni, S: 0.01% or less, Al: 0.004%.
Hereinafter, Si was limited to 0.05% or less.

Next, the characteristics of the alloy of the present invention will be specifically explained using representative examples.

Plasma arc melting in an inert gas atmosphere,
Alternatively, test materials having the chemical components shown in Table 1 were melted by vacuum induction melting or the like, and then ingots having the shape and dimensions shown in FIG. 1 were produced.

Next, each ingot is 20mm wide! After cutting to Tl/m, the material was hot rolled under the rolling conditions shown in Table 2. As shown in Table 1, the limit rolling rate of the material of the present invention was significantly improved over that of the commercially available material. Recognize. Further, when various properties such as corrosion resistance, high-temperature strength, and magnetic properties of these test materials were investigated, it was confirmed that the materials of the present invention were equivalent to or better than commercially available equivalent materials. Therefore, Si, S,
Reducing the content of Al and the like is a significant technical achievement in that hot workability can be improved without impairing the inherent properties of various nickel-based alloys.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an ingot for measuring the limit rolling rate, and FIG. 2 is a diagram showing the effects of %S, %Si, and %A1 on the limit rolling rate.

Claims (1)

[Claims] 1 In a nickel-based alloy containing Ni: 60% or more, S: 0.01% or less, Al: 0.004% or less, Si
: Nickel-based alloy with improved hot workability by adjusting to 0.05% or less.