JPS6045266B2 - Aluminum alloy with excellent wear resistance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aluminum alloy having excellent wear resistance.

Modern automobiles are being made lighter as part of their fuel efficiency measures, and light alloy materials such as aluminum alloys and magnesium alloys are often used for various parts.

Among these, aluminum alloy containing high-51 (Hyper Silumin) is used as it has wear resistance comparable to or higher than that of steel and cast iron, but conventional aluminum alloys of this type have There were problems with practicality due to insufficient abrasion resistance and poor machinability. Also,
As an aluminum alloy containing high Si,
There is a material disclosed in Japanese Patent No. 20244, which has good machinability, but has the problem that wear resistance and high temperature strength are insufficient.

The present invention provides an aluminum alloy with a new composition that can significantly improve wear resistance compared to conventional ones. Further, the present invention provides an aluminum alloy that has improved wear resistance and good machinability. The aluminum alloy of this invention has Si.
...3.5 to 20% by weight (all percentages below indicate weight%)
, Cu...4-5%, Mg...0.3-0.7%,
Ni...1.5-2.0%, Fe...less than 1% (O
%), Cr...0.4 to 0.8% The remainder essentially consists of Al, which is obtained by melting and casting by commonly used means, and is usually heat treated before use. It will be done. The reasons for limiting each component will be described below.

Si is added to improve wear resistance, but 20%
If it exceeds this value, it becomes brittle and has poor machinability.

When it is less than 13.5%, primary silicon crystallization decreases, resulting in insufficient wear resistance.

Cu is added to strengthen the matrix and increase high-temperature tensile strength, but if it exceeds 5%, it becomes brittle and has insufficient corrosion resistance.

If it is less than 4%, the base will not be strengthened and the wear resistance will be insufficient.

Mg is added to improve strength through age hardening, but
If the amount increases, the crystal grains of primary silicon tend to become coarser, so the upper limit is set to 0.7%.

When it is less than 0.3%, age hardenability is poor.

Ni is added to improve high temperature strength, and is 2.0
%, and if it is less than 1.5%, sufficient high temperature strength cannot be obtained.

Fe ensures toughness and prevents seizure of the die casting mold, and if it is 1% or more, the contact resistance is insufficient.

Cr suppresses the segregation of primary silicon and improves wear resistance, and if it exceeds 0.8%, a large amount of Cr compounds will crystallize, making it impossible to obtain sufficient strength.

When it is less than 0.4%, wear resistance is insufficient.

P is usually added once in an amount of about 0.4% to make the primary silicon crystal finer.

When it exceeds 0.4%, it becomes saturated.

Examples of the aluminum alloy of the present invention having the above composition will be described below. <Example 1> Si...19%, CU...4.5%, Mg...0
．． 5%, Ni...1.7%, Fe...0.3%, C
r...0.5% The aluminum alloy of the present invention, the remainder of which is essentially Al, was subjected to TeIB processing (heated at 500°C for 3 hours, cooled with water, and heated again at 180°C for 6 hours) to create a cylinder liner, and the following was prepared. A pliers test was conducted under the following conditions to test wear resistance.

Engine with 1000CC cylinder operating conditions: Ignition pliers test 700rpm (no load) x 3Hr300
0 rpm (17Ps) x 100Nr oil temperature: 60
~700C Water temperature: 700~8 (s) Oil Ni Engine oil 10W-30 (SD) Piston ring Ni Cast iron with Cr plating, C...
3.7%, Si...2.5%, Mn...0.7%,
P...0.4%, S...0.1%, B...0.0
Something consisting of 5% of ingredients.

For comparison, a cylinder liner made of a known aluminum alloy was used, and in Comparative Example 1, Si...17%, CU...
・4.5%, Mg...0.5% The balance was substantially made of A1 and was subjected to T6B processing in the same manner as in Example 1.

Comparative example; 2 is Si...19.3%, CU...1.
2%, Mg...1.25%, Ni...1.2%, F
e...0.23%, Cr...0.5% The remainder was substantially composed of N and was treated with T6 in the same manner as in Example 1. The results are shown in Figure 1.

From these results, it can be seen that the cylinder liner made of the aluminum alloy of the present invention has less than half the amount of wear compared to the cylinder liner of the comparative example made of the conventional aluminum alloy, and has excellent wear resistance. Also,
It can be seen that the amount of wear on the piston rings is also reduced when the cylinder liner made of the aluminum J alloy of the present invention is used, which also contributes to extending the life of the mating member. Example 2> Si...19%, CU...4.5%, Mg...0
．． 4%, Ni...1.54%, Fe...0.2%,
An aluminum alloy of the present invention consisting of 0.5% Cr and the remainder substantially A1 was subjected to T6 treatment in the same manner as in Example 1 to prepare a disk-shaped test piece.

This test piece was rotated at 200 rpm to 2,500 rpm, and mating members made of various materials were brought into contact with each other by pressing once, and the amount of wear of the test piece was measured. For comparison, the same aluminum alloy test piece as Comparative Examples 1 and 2 used in Example 1 was used. The material and composition of the mating material are as follows. Compatible material 1 (aluminum-impregnated carbon) Carbon sintered body impregnated with aluminum at C...67.5% and A1...32.5%.

Compatible material 2 (aluminum impregnated carbon) C...65%, A]...35% carbon powder packed in an aluminum container and impregnated by autoclave method Compatible material 3 (P-B cast iron) C... 3.3%, Si...2.
1%, Mn... 1%, P... 0.1%, B...
・0.3% Remaining mge Mating material 4 (P-B cast iron) C...3.3%, Si...2.1%, Mn...<
1%, P...0.1%, B...0.5% Remaining material 5 (chill casting) C...3.5%, Si...2.2%, Mn...1
．． 0%, Cr...0.5%, MO...1.5%, C
U...1.0%, Ni...1.0% Cast iron with balance Fe, surface hardness 1 (V8OO).

Compatible material 6 (chill casting) Cast iron with the same composition as counterpart material 5 and surface hardness HV9OO.

Compatible material 6 (chilled casting) Cast iron with the same composition as counterpart material 5, subjected to strain relief treatment (590℃
Hardness HV65O after drying and air cooling.

Compatible material 7 (chill casting) Cast iron with the same composition as counterpart material 5, with hardness HV78O after strain relief treatment (50 straight DQ7, air cooling).

The results are shown in Table 1. As a result, the test piece made of the aluminum alloy of the present invention showed a small amount of wear, and in particular showed a stable amount of wear even when the mating material was changed, and had superior wear resistance compared to Comparative Examples 1 and 2. I know that there is. <Example 3
> Si...15%, CU...4.7%, Mg...0
．． 7%, Ni...2.0%, Fe...0.2%, C
r...0.8% An aluminum alloy of the present invention consisting essentially of A1 with the remainder being subjected to T6 treatment in the same manner as in Example 1 to prepare a test piece.

This test piece was combined with a rotating disk made of SCr22fl4 and carburized and quenched and having a hardness of RC61 to 62, and the seizure characteristics were tested using a wet pin desk method. Comparative Examples 1 and 2 were made of the same aluminum alloy as used in Example 1, Comparative Example 3 was made of FCD45N, and Comparative Example 4 was made of FCD45N.
is obtained by applying MO spraying to FCD45N. The results are shown in Figure 2. As a result, it can be seen that the test piece made of the aluminum alloy of the present invention exhibits significantly higher seizure characteristics than Comparative Examples 1 and 2, and has excellent wear resistance. <
Example 4> Si...14%, CU...4.5%, Mg...0
．． 6%, Ni...1.8%, Fe...0.2%, C
r...0.8% The aluminum alloy of the present invention, the remainder of which was essentially Al, was T-milled in the same manner as in Example 1 to prepare a test piece, and this test piece was used to test machinability.

Note that Comparative Examples 1 and 2 were made of the same aluminum alloy as that used in Example 1, and Comparative Example 3 was made of cast iron corresponding to FC2O. The results are shown in Table 2.

As a result, the test piece made of the aluminum alloy of the present invention was
The cutting speed is the same as or higher than Comparative Examples 1 to 3, and it can be seen that the aluminum alloy of the present invention has good characteristics in terms of machinability. As described above, the aluminum alloy of the present invention has significantly higher wear resistance than conventional aluminum alloys, and also has good machinability properties, making it an excellent wear-resistant material. It is an aluminum alloy.

[Brief explanation of drawings]

Figure 1 is a diagram comparing the amount of wear measured between an aluminum alloy cylinder liner and a cast iron piston ring.

Claims (1)

[Claims] 1 Si...13.5 to 20% by weight (all percentages below indicate weight%) Cu...4 to 5%, Mg...0.3 to
0.7%, Ni...1.5-2%, Fe...less than 1% (not including 0%), Cr...0.4-0.8%, the remainder substantially more than Al Made of aluminum alloy with excellent wear resistance.