JPS6254387B2 - - Google Patents

Description

[Detailed description of the invention]

This invention has particularly excellent molten glass erosion resistance, and is therefore suitable for use in manufacturing molten glass contact members such as spinners for forming glass fibers.
This relates to Co-based heat-resistant alloys. Generally, glass fibers are made by charging molten glass heated to about 1000°C into a spinner, rotating the spinner at a high speed of about 1700 rpm, and drilling radially along the side wall of the spinner. Since the spinner is formed by ejecting molten glass using centrifugal force from a large number of pores, the spinner is required to have high-temperature oxidation resistance, high-temperature strength, especially high-temperature creep rapture strength, and molten glass resistance. It is required to have erosive properties. Traditionally, the typical alloy used to manufacture this glass fiber molding spinner is 28% by weight.
There is a Co-based heat-resistant alloy with a composition consisting of Cr-13%Ni-10%W-1.5%Ta-Co, but this conventional Co-based heat-resistant alloy has a particularly poor resistance to molten glass erosion. The pore diameter of the pores in the spinner side wall became larger than the allowable limit relatively early, and the service life was reached. Therefore, from the above-mentioned viewpoints, the present inventors conducted research to develop an alloy with high-temperature oxidation resistance, high-temperature strength (high-temperature creep rupture strength), and molten glass erosion resistance. Contains, in weight%, C: 0.05-0.6%, Si: 0.1-2%, Cr: 18-24%, W: 10-20%, Ni: 18-24%, Hf: 0.5-5%. , further contains either or both of Mn: 0.1-2%, rare earth elements: 0.005-0.1%, and the rest is
The Co-based heat-resistant alloy, which has a composition consisting of Co and inevitable impurities, not only has excellent high-temperature oxidation resistance and high-temperature strength (high-temperature creep rapture strength), but also has excellent molten glass erosion resistance.
Therefore, we have found that when this Co-based heat-resistant alloy is used in the production of molten glass contact parts, particularly spinners for forming glass fibers, the resulting parts exhibit excellent performance over an extremely long period of time. It was. This invention was made based on the above knowledge, and the reason why the component composition range was limited as described above will be explained below. (a) C The C component includes Cr, Cr, in addition to solid solution in the base material.
It combines with W and Hf to form carbides, which has the effect of strengthening grains and grain boundaries, improving high-temperature strength, and further improving weldability and castability. but
If the content is less than 0.05%, the desired effect cannot be obtained, while if the content exceeds 0.6%, the toughness will deteriorate, so the content should be reduced to 0.05%.
It was set at ~0.6%. (b) Si In addition to having a deoxidizing effect, the Si component also has the effect of improving the fluidity of the molten metal and further improving the high-temperature oxidation resistance, but if its content is less than 0.1%, the desired effect is not achieved. On the other hand, if the content exceeds 2%, the toughness and weldability will deteriorate.
It was set at 2%. (c) Cr The Cr component is an essential austenite component for ensuring excellent high-temperature oxidation resistance, but if its content is less than 18%, the desired excellent high-temperature oxidation resistance cannot be achieved. zu, on the other hand 25
Since high-temperature strength and toughness will rapidly decrease if the content exceeds 18% to 25%. (d) W The W component combines with C to form MC type carbide, which is a high melting point carbide, while M ₇ C ₃ type and M ₂₃ C _{6 type} carbide.
It has the effect of suppressing the formation of low-melting point carbides in the mold, improving high-temperature strength, and solid-dissolving into the austenite matrix to strengthen it. However, if its content is less than 10%, the desired effect is not achieved. However, if the content exceeds 20%, no effect can be obtained.
Not only does high-temperature oxidation resistance rapidly deteriorate, but also intermetallic compounds such as σ phase, which cause toughness deterioration, begin to form.
Its content was set at 10-20%. (e) Ni The Ni component has the effect of improving high-temperature strength when coexisting with Cr, forming an austenite matrix, stabilizing it well, and improving workability. If it is less than 24%, the desired effect cannot be obtained.
Since high-temperature oxidation resistance will deteriorate if the content exceeds 18% to 24%. (f) Hf The Hf component does not form MC type or M ₇ C ₃ type eutectic carbide, but forms MC type primary carbide, which is a high melting point carbide, to improve high temperature oxidation resistance and high temperature strength. It has the effect of improving the corrosion resistance of molten glass and further improving the erosion resistance of molten glass.
If the content is less than 0.5%, the desired effect cannot be obtained in the above action, and on the other hand, if the content exceeds 5%, the effect of further improving the action cannot be obtained.
Considering economic efficiency, the content was determined to be 0.5 to 5%. (g) Mn In addition to having a strong deoxidizing effect, the Mn component has the effect of solid-dissolving into the austenite matrix, stabilizing it, and improving toughness.
It is included as necessary when these properties are required, but if the content is less than 0.1%, the desired effect will not be obtained, while if the content exceeds 2%, high temperature oxidation resistance Since a tendency toward deterioration appears in the quality, the content should be reduced.
It was set at 0.1-2%. (h) Rare earth elements These components have the effect of further improving high-temperature oxidation resistance, especially when coexisting with Hf, so they may be included as necessary when particularly excellent high-temperature oxidation resistance is required. However, if the content is less than 0.005%, the desired effect cannot be obtained, while if the content exceeds 0.1%, the castability and processability tend to deteriorate. Amount 0.005~0.1
%. Furthermore, among the inevitable impurities in the Co-based heat-resistant alloy of this invention, especially regarding Fe, 3%
Even if it is contained up to 3%, the alloy properties will not be impaired in any way, so in consideration of economic efficiency, it may be actively included in the range of up to 3%. Next, the Co-based heat-resistant alloy of the present invention will be specifically explained with reference to Examples. Examples Co-based heat-resistant alloys 1 to 21 of the present invention having the compositions shown in Table 1 by ordinary melting method
And Comparative Co-based heat-resistant alloys 1 to 9 were melted, and using the lost wax precision casting method, the outer diameter of the parallel part was 7.
mmφ x parallel length: 50mm x chuck outside diameter: 25mm
A test piece material with dimensions of φ x total length: 90 mm was cast. Next, a creep lap tear test piece was cut from this test piece material for the purpose of evaluating high temperature strength, and using this test piece, atmosphere: air, heating temperature: 1100℃, added load stress: 3.5Kg/mm ² A creep burst test was conducted under the following conditions to measure the rupture life. In addition, a test piece with dimensions of diameter: 10 mmφ x height: 10 mm was cut out from the chuck part of the test piece after the above-mentioned creep rapture test, and using this test piece,
After holding in the air at a temperature of 1100°C for 10 hours, one cycle of descaling was performed, and a high-temperature oxidation resistance test was conducted to measure the oxidation loss after 10 cycles. Furthermore, for the purpose of evaluating the molten glass erosion resistance, the immersion part dimension was 6 mm in diameter from the above test piece material.
A test piece with mmφ x length: 16 mm was cut out, and this test piece was subjected to a molten glass immersion test in which it was immersed in molten glass at a temperature of 1120°C for 120 hours.

[Table] The percentage of corrosion loss was measured. These measurement results are also shown in Table 1. From the results shown in Table 1, the Co-based heat-resistant alloys 1 to 21 of the present invention all have excellent high-temperature strength, high-temperature oxidation resistance, and molten glass erosion resistance, while the comparative Co As seen in Base Heat Resistant Alloys 1 to 9, if the content of any of the constituent components (those marked with * in Table 1) falls outside the scope of this invention, some of the above-mentioned properties may change. It is clear that at least one of the characteristics will be inferior. As mentioned above, the Co-based heat-resistant alloy of the present invention is
It has excellent high-temperature strength and high-temperature oxidation resistance, as well as excellent resistance to molten glass erosion, so it is especially used in the manufacture of molten glass contact parts such as spinners for glass fiber molding, which require these properties. In some cases, they exhibit excellent performance over an extremely long period of time.

Claims (1)

[Claims] 1 Contains C: 0.05-0.6%, Si: 0.1-2%, Cr: 18-24%, W: 10-20%, Ni: 18-24%, Hf: 0.5-5%. A Co-based heat-resistant alloy for a molten glass contact member, characterized in that the remainder is Co and non-wall impurities (weight %). 2 Contains C: 0.05-0.6%, Si: 0.1-2%, Cr: 18-24%, W: 10-20%, Ni: 18-24%, Hf: 0.5-5%, and further contains Mn. A Co-based heat-resistant alloy for a molten glass contact member, characterized in that it contains: 0.1 to 2%, and the remainder consists of Co and non-wall impurities (weight %). 3 Contains C: 0.05-0.6%, Si: 0.1-2%, Cr: 18-24%, W: 10-20%, Ni: 18-24%, Hf: 0.5-5%, and further contains rare earth elements. 1. A Co-based heat-resistant alloy for a molten glass contact member, characterized in that it contains one or more of the following elements: 0.005 to 0.1%, with the remainder consisting of Co and non-wall impurities (weight percent). 4 Contains C: 0.05-0.6%, Si: 0.1-2%, Cr: 18-24%, W: 10-20%, Ni: 18-24%, Hf: 0.5-5%, and further contains Mn. 0.1 to 2%, and one or more rare earth elements: 0.005 to 0.1%, with the remainder consisting of Co and unavoidable impurities (weight %). Co-based heat-resistant alloy.