JPH0348254B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a platinum-based alloy that is used in various industrial instruments that require high strength. [Prior Art] Conventional high-strength platinum-based alloys include platinum-iridium alloys and platinum-rhodium alloys, whose compositions are 90% Pt-Ir and 90% Pt-Rh.
is the most common one. However, these known alloys cannot be said to have sufficiently satisfactory hardness and tensile strength.
In addition, the strength and yield strength at high temperatures are low, and the recrystallization temperature is low, causing defects such as coarse crystal grains, as well as problems such as pinholes and blowholes easily forming in the ingot. . [Problems to be Solved by the Invention] The present invention has investigated the drawbacks of the above-mentioned high-strength platinum-based alloys, and has solved the above-mentioned problems by adding an appropriate amount of a new element to Pt to create a ternary or higher alloy. The aim is to significantly improve the deficiencies of the conventional example. [Means for Solving the Problems] In order to achieve the above object, the present invention incorporates Pt into Pt.
Ni is added in a weight ratio of 1 to 15%, and one or more elements selected from Ti, Zr, Cr, and Mn are added in a weight ratio of 0.05 to 5%, and the sum of the added elements is added in a weight ratio of 1 to 15%. This provides a high-strength platinum-based alloy characterized by a platinum content in the range of 1 to 20%. [Function] In the present invention, Pt and the Ni added thereto are all solid solution type alloys, and by adding Ni to Pt, the matrix is strengthened. By selecting one or more of Zr, Cr, and Mn, the recrystallization temperature becomes higher and the material becomes microcrystalline.This is the main factor that reduces the amount of deflection at high temperatures and increases the strength at high temperatures. Furthermore, as mentioned above, the mechanical properties such as hardness and tensile strength at room temperature were significantly improved as described below because of Ni, Ti, Zr,
This is thought to be due to the dramatic improvement in low temperature age hardenability due to the combined addition effect with selected elements from the Cr and Mn groups. Next, the reason why Ni is added in an amount of 1 to 15% relative to Pt is that if it exceeds 15%, corrosion resistance, which is the most important property for a platinum alloy, will be impaired, causing practical problems. This is because if the addition amount is less than 1%, other reinforcing effects of Pt are not exhibited. Furthermore, regarding the addition amount of the latter selected element, if it exceeds the above-mentioned 5%, the castability of the alloy will be inhibited and work hardening will become severe, making plastic working difficult.If it is less than 0.05%, Ni It becomes impossible to obtain the effect of combined addition with. [Example] The total amount of one sample was 400 g, and the platinum-based alloys shown in the attached tables (a) to (I) were melted and cast in an arc melting furnace after weighing the component elements for each composition. The ingot according to the attached table above was formed into a plate shape of 10 mm thick, 30 mm wide, and 60 mm long by hot casting and cutting, and then annealed and rolled at 1000 to 1200°C repeatedly to form a plate with a thickness of 0.5 mm. The processing steps for each of these samples were all unified, and the final processing rate was 65%. The results of measuring various properties of the samples obtained in this way are shown in the attached table.Here, regarding the hardness and tensile strength tests, samples (b) to (I) had a The material used was aged at a temperature of 450°C. Note that since sample (a) has almost no age hardening ability, measurements were made on the as-processed sample. In addition, the following method was adopted for measuring high-temperature strength. The above-mentioned sample was cut to a width of 20 mm and a length of 60 mm, and a plate 2 with a through hole 1 as shown in Fig. 1 was cut into a piece with a width of 20 mm and a length of 60 mm.
A plate 3 made of the same sample cut into pieces of 20 mm and 150 mm in length was fixed at the welding part 4 with a small precision torch burner so as to form a T-shape as shown in the figure, and then the through hole 1 was
This was suspended in a high temperature furnace using a hanging rod 5 inserted through the plate, and kept at 1450°C for 1 hour. After cooling, both ends 3' and 3' of the plate 3 viewed from the front were Measured the amount of deflection. Further, the crystal grain size was measured using a micrometer after polishing and etching the cross section of the sample that had undergone the deflection test as described above.

〔Effect of the invention〕

Since the present invention is configured as described above and can be implemented as in the above embodiments, the mechanical properties are extremely superior not only at room temperature but also in a high temperature range, and the crystal grain size is small, as compared to the conventional example. Even during the above-mentioned melting and casting processes, it was confirmed that gas release was good, there were few pinholes and blowholes, workability was good, and the casting surface of the cast ingot was smooth. .

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a material for measuring high-temperature strength made of a platinum-based alloy according to the present invention, Fig. 2 is a perspective view of the same material with a hanging rod inserted through it, and Fig. 3 is a
FIG. 3 is a front view of the one shown in the figure after high-temperature treatment.

Claims (1)

[Claims] 1 Pt contains 1 to 15% Ni by weight, Ti, Zr,
A high-strength platinum-based alloy characterized in that 0.05 to 5% of one or more elements selected from Cr and Mn are added, and the total amount of the added elements is in the range of 1 to 20%.