JPS5874575A - Plasticity working tool for aluminum and aluminum alloy - 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 plastic working tool used for drawing, wire drawing, wire pressing, extrusion, or gui-casting of aluminum and alloys mainly composed of aluminum rough alloys.

Conventionally, cemented carbide medium die steel high speed steel has been used as a plastic working tool for aluminum and aluminum alloys.

However, due to the economic requirements of manufacturing conditions for mass-produced products such as wire drawing rods, etc., tb has become stricter year by year, and accordingly, heat resistance and wear resistance are also required for plastic working tools.

Welding is the major cause of damage to tools when plastic working aluminum and aluminum alloys.

Particularly during hot working, cemented carbide and die steel high speed steel are subject to repeated welding and separation, which causes cracks due to peeling phenomena called syspauling, fatigue phenomena, and thermal cracks due to thermal cycling μ, which can shorten their service life. be. - The inventors of the present invention have conducted studies to solve the above-mentioned drawbacks of conventional plastic working tools made of aluminum or aluminum alloy all around, and have arrived at the present invention.

That is, according to this invention, as the raw material composition of the plastic working tool, 81
1N4060% by weight or more and MUIN, MUITCH, y=
os.

MpO, Oak, '1yes, TzOz, HtO, 8
10. Coos, Boo, T.J.N.

40% by weight or less of 2 or more types of 111 such as Mp, N, and MoI, or KWO and/or Mo.
It is characterized by containing 201% by weight or less of C.

To explain the present invention in detail, first, it is important that the tool be made of a material that causes the welding phenomenon to be as small as possible.

However, Cefmic has low weldability to metals.

Among them, the most common Afi/Mina-based Nanafumitsuku Co., Ltd. has low strength and high stress, so it cannot withstand use due to reliability problems in plastic processing where it is subjected to blows.

Furthermore, alumina-based ceramics have poor thermal shock resistance, making them unsuitable for hot tools that undergo many thermal cycles.

I tried testing with various ceramic tools and found 8.
It was discovered that a ceramic mainly composed of 11N4 exhibits far superior performance as a plastic working tool for aluminum and aluminum alloys (4) than the cemented carbide and die steel conventionally used.

In this invention, 81. used as the main material. N.

Two methods are known: a sintering method in which a molded body of 81 metal powder is nitrided, and a powder metallurgy method in which 8S N4 and additives are mixed.

The former method leaves more than 10% of pores, and is inappropriate for the purpose of the present invention.

The reason for this is that due to insufficient J strength, coarse tore occurs on the surface, leaving the surface of the product rough.

In the latter manufacturing method, it is known that the properties are greatly influenced by the rounding process using additives.

However, basically, if high strength and impact resistance are required, it is necessary to use 81 sN+ in which K is at least 0% by weight. □Next, as an additive to be used for 60% by weight or more of 81sNallC, MuI
Known substances such as N, Muzoos, YsOs, BhO* OaO* are effective, but the amount added is 1 to 40
A weight of 96 (preferably S to 20% by weight) is suitable.

If a is less than 1% by weight, sufficient strength cannot be obtained;
This is because if it exceeds 0% by weight, it becomes brittle.

Although dilated materials such as WC+M swelled materials are also effective in improving the strength of the entire tool, they have a problem with reaction with aluminum, so the amount thereof is preferably 20% by weight or less.

In such a tool, if any holes remain, the strength will be low (1 kS) and the reliability will also be reduced, so it is better to have as high a density as possible.

However, if the pore size is within 5g6, there is no effect.

Additionally, metals such as B, F*, (3a, and Nt) as additives can be effective if used in small amounts.

Regarding 8JsNa, its crystal system can be used for any of the four effects regardless of whether it is the A type or the Ill type.

The present invention will be explained in detail below with reference to Examples.

Example 1 80% by weight of commercially available 5IBN4 powder, 10% by weight of Muro Os, and 10% by weight of Yro Os were weighed and thoroughly mixed in a PaulmiP, then static pressure molded at a pressure of It/-, and then nitrogen A hot-rolling wire μ of aluminum 5005 wire was prepared by sintering at 1800° C. for 4 hours under a pressure of 1 atmosphere.

The temperature of the abrasive material was sooC, the area reduction rate was 86g6, and the abrasiveness was 16 m/sea. □The life of the obtained hot rolling roll was due to roughness of the low μ surface, but it was possible to roll 4800 tons during that time.

Example: An aluminum rolling rope was prepared using 8QN4 sintered body using 84@N4 powder and various sintering aids shown in Table 1 in the same manner as in Example 1, and its life (rolling temperature: 500 ′
When we investigated the amount of rolling required to reach the end of the life and the causes of the life, we obtained the results shown in Table 1.

For comparison, the lifespan of commercially available low μ made of cemented carbide and low μ made of alloy copper is also shown.

Example 8 Commercially available 84N4 powder 80% by weight, 8IC 10% by weight, Y
C) 5% by weight of s and 5% by weight of Mpo were thoroughly mixed in a ball mill, statically molded at a pressure of 1/-, and then sintered at 1800°C for 4 hours under a nitrogen pressure of 1 atm. A minium-5oospO hot extrusion die was created.

The life of the obtained die was investigated with respect to the amount of rolling, and the life of the commercially available cemented carbide die was found to be 1,560 tons, while the life of the die according to the present invention was 7,800 tons.
Even after using 100 ton, the service life did not come to an end.

Example 4 75% by weight of commercially available 81N4 powder, 20% by weight of Ajyuki 0s, and 5% by weight of MuiN were weighed, thoroughly mixed in a ball mill, and then mixed with 81BN4 in the same manner as in Example 8. A guide roll made of a sintered body was obtained.

When this guide roll was compared with commercially available alloy steel guide rolls and alumina guide rolls, the results shown in Table 2 were obtained. 2Ili was demonstrated to be extremely long.

Table 2

Claims (1)

[Scope of Claims] (1) A plastic tool for aluminum and aluminum alloys, characterized by containing 60% by weight or more of 811N4 and having 6% or less of pores. (MujN, Mut srs for Takumi 8Js N4 K,
YsOs, MFO. OaO, Zrob, TIO Kura, MFO Hiroshi, 8IC, 0a
Ks, Boo. Aluminum and aluminum according to claim 1, containing 1 to 40% by weight of one or more types such as 'j t N, MF s N
Plastic processing tool for minium alloy. (8) For use in aluminum alloys and aluminum alloys as described in claim 1 J [or claim 2], which contain 20% by weight or less of we and/or less than 20% by weight based on 81N4. Plastic processing tools.