JPS60200946A - Aluminum alloy for electric conduction - 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 The present invention relates to a conductive aluminum alloy with high electrical conductivity and h-strength.

In recent years, as the rotation speed of squirrel cage electric motors has increased, the diameter of the squirrel cage rotor has become smaller, and the slot holes provided in the squirrel cage rotor have become smaller, a few millimeters in diameter. However, the secondary conductor of the squirrel cage rotor formed by casting into the slot hole is desired to have high electrical conductivity and high strength.

However, if the secondary conductor of the squirrel-cage rotor is made of aluminum, which contains unavoidable impurities, the squirrel-cage rotor slotper or shorting ring will break or break due to centrifugal force during high-speed rotation. For this reason, when a high-strength aluminum base alloy such as copper-silicon-aluminum is used, the air conductivity decreases markedly and the heat loss of the horn-shaped rotor conductor increases.

The inventors of the present invention conducted various studies in consideration of these points, and found that copper of 0.2 to 0.7% by weight and 0.2 to 6.0% of copper
By forming the conductor of the squirrel-cage rotor by die-casting an aluminum-based alloy consisting of nickel and the remainder aluminum, it is possible to conduct a high-strength squirrel-cage rotor without reducing electrical conductivity. I have succeeded in obtaining this, so I would like to disclose it here.

Copper in the conductive aluminum alloy of the present invention is dissolved in aluminum to form a copper-aluminum alloy, thereby increasing the strength of the conductive aluminum alloy without reducing electrical conductivity. When the amount of copper added exceeds 0.7%, two cracks occur in the conductive aluminum alloy, and when used as a secondary conductor of a squirrel cage rotor, a leak occurs. ′! 1: If the amount of copper added is less than 0.2 inch, the strength of the aluminum alloy used for conducting cannot be sufficiently increased, so at least 0.2 inch is required. Nickel does not form a solid solution in aluminum, but precipitates between the primary crystals of the copper-aluminum alloy as an intermetallic compound of aluminum and nickel, significantly improving electrical conductivity control of conductive aluminum alloys without reducing the overall control. . If the amount of nickel 'Mi IJN exceeds 6%, the inter-gold compound of aluminum and nickel that precipitates becomes coarse and micro-cracks occur during casting, causing the conductive aluminum base metal to break. If the amount of nickel added is 0.2%, the strength of the conductive aluminum alloy will not be sufficiently improved, so a minimum of 0.2% is necessary.

Examples will be described in detail below.

After At alloys containing AtKCu and Ni in various compositions with a purity of 99.9% were melted in the atmosphere using a graphite rutsuho,
Cast into a 40x40x200m mold, and from this J I
A No. S4 tensile test piece was prepared, and its tensile strength and electrical conductivity were measured.

The 17'c1 molten metal was poured into a ring test mold and a casting crack test was carried out.

Some examples of these results are shown in Table 1 in comparison with all known alloys (comparative examples).

The purpose of the present invention is that both tensile strength and electrical conductivity must be high, and therefore lower limits are set for each property. That is, a material that satisfies the object of the present invention has a tensile strength of 9, Oh/yxi or more, and a thermal conductivity of about 40 or more.

Therefore, the first condition for an alloy suitable for the purpose of the present invention is that it satisfies the above conditions, and furthermore, it is necessary that casting cracks do not occur.

Therefore, as shown in Table 1, the composition of the alloy of the present invention is CuO, 2-0,71/NiO, 2-6 in weight percent.
．． The range was set to 0. The basis for this is that if one of Cu or Ni elements does not meet this composition, the strength will be insufficient, and if even one element exceeds this composition, P casting cracks will occur with a wide width between the liquidus line and the solidus line. By what happens. Comparative example 1
Since it contains Cof, the manufacturing cost is high. ! *
% Comparative Examples 2 and 3 have low electrical conductivity.

As can be seen from the above examples, if a high-speed morph consisting of a υ squirrel-cage rotor is manufactured using such materials, it can be compared with the conventional At
It is clear that higher reliability can be obtained with lower loss than cast alloys.

This article has been explained in relation to the secondary conductor of the squirrel cage rotor, but it is not limited to this, and is useful when manufacturing industrial products that require high strength and high electrical conductivity, such as 2 isers. It is made of aluminum alloy.

In addition, although only the results of mold gravity casting were shown in and\, similar results were obtained when actual kfA was performed using high-pressure gravity casting or sand bottle casting.

Patent applicant: Yaskawa Electric Manufacturing Co., Ltd.

Claims (1)

[Claims] Conductive aluminum alloy consisting of 0.2 to 0.7% copper, 0.2 to 6.0% nickel, balance aluminum