JPS63290236A - Ni based cast alloy for dentistry - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides dental N, which has the properties required for dental parts such as dental beds and crowns, and which has excellent castability.
This relates to i-base casting alloys.

[Conventional technology]

In general, the above-mentioned dental components have the strength to not be deformed by the pressure of occlusion when actually installed in the oral cavity, the corrosion resistance to not corrode by intraoral secretions, etc., and are ground after being cast. Since properties such as toughness while maintaining a certain degree of hardness are required, Ni-Cr based casting alloys having these properties are used in the VJ construction of these members.

[Problem that the invention seeks to solve]

However, this conventional dental N i -Cr W casting alloy has an extremely high melting point and poor flowability, so when casting, combined with the complicated shape of the casting, it is difficult to control the molten metal temperature. It must be cast at a high height, and as a result, it is easy to seize with the mold, making it difficult to produce castings with a clean surface, and finishing grinding requires considerable effort and time. Met.

[Means for solving problems]

Therefore, from the above-mentioned viewpoint, the present inventors focused on the above-mentioned Ni-Cr-based casting alloy, which has the properties required for dental components, and found that it has excellent castability, that is, a relatively low melting rate. It exhibits excellent flowability even when cast at high temperatures, and can be used for complex shapes! As a result of research to develop an alloy that can produce 7F products with a clean casting surface and in a sound manner, we found that Si: 0.1 to 6% in weight% (hereinafter % indicates weight%).

Mn: 0.1-3%.

Cr: 20-37%.

MO: 1-20%.

1”f: 0.005-6%.

3: 0.0001-0.5%.

Contains, and if necessary, W: 0.1 to 10%.

One or more of Ti, Nb, and Ta: 0.1 to 12%.

A Ni-based casting alloy containing one or both of the following, with the remainder consisting of Ni and unavoidable impurities:
It has the strength, corrosion resistance, toughness, and hardness required for dental parts, has good muddy flow properties, and has excellent castability, so it can manufacture dental parts with complex shapes with a clean casting surface. We obtained the knowledge that it is possible to do this.

This invention was made based on the above knowledge, and the reason why the component composition was limited as described above will be explained below.

(a) In addition to having a deoxidizing effect, the Si 3f component has the effect of lowering the melting point of the alloy, improving flowability, and thereby improving castability, but if its content is less than 0.1%, The desired effect cannot be obtained in the above action, and on the other hand, if the content exceeds 6%, C
Since the toughness of the alloy decreases in relation to the r content, the content of nff1e was determined to be 0.1 to 6%.

(b) Mn In addition to having a deoxidizing effect like the 3f component, the Mn component also has a deoxidizing effect.
It forms a solid solution in the base material and has the effect of stabilizing the austenite in the base material, but if its content is less than 0.1%, the desired effect cannot be obtained; on the other hand, even if the content exceeds 3%. The content was set at 0.1 to 3% because not only the effect of further improvement could not be obtained due to the above action, but also the corrosion resistance tended to deteriorate.

(C) Or The Cr component has the effect of forming a solid solution in the base material, strengthening it, improving strength, and significantly improving corrosion resistance, but if the content Φ is less than 20%, the above-mentioned The desired effect could not be obtained, and if the content exceeded 37%, the toughness would tend to decrease, so the content was set at 20 to 37%.

(d)M.

Like the C component, the MO acid component also acts as a solid solution in the base material to strengthen it and improve its strength, but if its content is less than 1%, the desired strength and hardness cannot be achieved. On the other hand, if the content exceeds 20%, the toughness of the alloy will decrease, so the content should be reduced from 1 to 20%.
It was determined that

(e. However, if the content is less than 0.005%, the desired effect cannot be obtained, and if the content exceeds 6%, no further improvement effect will be obtained. Considering economic efficiency, the content was determined to be 0,005 to 6%.

(f) Part of the B-day component dissolves in solid solution in the base material, improving strength, forming borides, improving hardness, and contributing to rough flowability, improving castability. It has the effect of further improving it, but does it contain it? If the content is less than 0.0001%, the desired effect will not be achieved, and if the content exceeds -7J0.5%, the toughness will tend to decrease. It was set at 0001 to 0.5%.

(()) Like the Cr and MO acid components, the W component has the effect of forming a solid solution in the base material, strengthening it, and improving its strength, so it is especially necessary when these properties are required. However, if the content is less than 0.1%, the desired effect of improving the above action cannot be obtained, while if the content exceeds 10%, the toughness will be reduced. Its content R
was set at 0.1 to 10%.

(h) Ti, Nb, and Ta These components have the effect of significantly suppressing the growth of crystal grains in the base material and, in fact, making the crystal grains finer, so they may be used as necessary when these properties are required. However, the content 3 is 0
．． If it is less than 1%, the desired effect of improving the above action cannot be obtained;
On the other hand, if the W content exceeds 12%, the toughness of the alloy decreases, so the W content was determined to be 0.1 to 12%.

In addition, Zr component may be contained as an unavoidable impurity, but if the content exceeds 0.3%, the toughness and v
Zr content 1 has a negative effect on I-forming property.
must not exceed 0.3%. Further, Fe1CO may be contained depending on the melted raw material used, but there is no problem if the content is up to 3%.

〔Example〕

Next, the Ni-based casting alloy of the present invention will be specifically explained using examples.

The Ni-based cast alloys 1 to 1 of the present invention having the respective compositions shown in Table 1 were cast in an ordinary high-frequency melting furnace in the atmosphere.
Molten metals of No. 25 and conventional Ni-based VI alloy were prepared and then cast into sand molds to produce test pieces for hardness measurement, test pieces for tensile strength measurement, and materials for flow measurement No. 32, respectively.

Next, using these test pieces, we measured Vickers hardness at room temperature in order to evaluate wear resistance, and tensile strength, 0.2% proof stress, and elongation in order to evaluate strength and toughness. Furthermore, for the purpose of evaluating castability, the above material was heated and melted at a relatively low temperature of 1450°C, at which almost no reaction with the mold occurs, and immediately after reaching this temperature, it was placed inside a mold made of phosphate material. Diameter formed: o, smφ×
Cast in a cavity with a length of 70 tna using a small high-frequency centrifugal casting chamber in an argon atmosphere,
The flow length of each was measured. The results of these measurements are shown in Table 2. In addition, the evaluation of castability is based on the lifting flow length of 3.
The evaluation was made with an X mark if it was less than 0#11, a mark ○ if it was 30 to less than 50M, and a mark ◎ if it was 50M or more.

〔Effect of the invention〕

From the results shown in Table 2, the Ni-based cast alloys 1 to 1 of the present invention
No. 25 has hardness equal to or better than conventional Ni-based casting alloys, high strength, and l! It is clear that the alloy has a toughness of 3i and has much better castability than the conventional Ni-based casting alloy.

As described above, the Ni-based casting alloy of the present invention not only provides the excellent wear resistance, corrosion resistance, and toughness required for dental components, but also exhibits even better castability, which is essential for the production thereof. It is.

Claims (4)

[Claims] (1) Si: 0.1-6%, Mn: 0.1-3%, Cr: 20-37%, Mo: 1-20%. A dental Ni-based casting characterized by having a composition (the above weight %) containing Hf: 0.005 to 6%, B: 0.0001 to 0.5%, and the remainder consisting of Ni and unavoidable impurities. alloy. (2) Si: 0.1-6%, Mn: 0.1-3%, Cr: 20-37%, Mo: 1-20%, Hf: 0.005-6%, B: 0.0001- 0.5%, and further contains W: 0.1 to 10%, and the remainder is Ni and unavoidable impurities (weight %). alloy. (3) Si: 0.1-6%, Mn: 0.1-3%, Cr: 20-37%, Mo: 1-20%, Hf: 0.005-6%, B: 0.0001- 0.5%, and further contains one or more of Ti, Nb, and Ta: 0.1 to 12%, with the remainder consisting of Ni and unavoidable impurities (by weight) %) for dental use. (4) Si: 0.1-6%, Mn: 0.1-3%, Cr: 20-37%, Mo: 1-20%, Hf: 0.005-6%, B: 0.0001- 0.5%, and further contains W: 0.1 to 10%, and one or more of Ti, Nb, and Ta: 0.1 to 12%, and the remainder is A dental Ni-based casting alloy characterized by having a composition (the above weight %) consisting of Ni and unavoidable impurities.