JPH01152235A - High-strength and wear-resistant aluminum alloy continuous cast material - Google Patents

Abstract

PURPOSE:To obtain the above cast material by adding and alloying specific amounts of Si, Cu, Mg, Fe, Mn and B or furthermore one kind between Sr and Na to Al. CONSTITUTION:The Al alloy continuous cast material contg., by weight, 7.5-13.5% Si, 3.0-6.0% Cu, 0.3-1.0% Mg, 0.2-0.5% Fe, 0.2-0.5% Mn and 0.002-0.03% B and either one kind between 0.003-0.015% Sr and 0.003-0.015% N is used as the material for a piston, cylinder, etc., as the parts for an automobile. By the presence of Fe and Mn, eutectic Si and Si-Mn-Fe crystallization are fined to <=30mum to obtain the Al alloy continuous cast material having excellent strength and wear resistance.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a high-strength, wear-resistant aluminum alloy continuous casting material, and more specifically, a light fit, wear resistance, and high strength are required. The present invention relates to a high-strength, wear-resistant aluminum alloy continuous casting material used, for example, in pistons, cylinders, etc., and in automobile parts.

[Prior Art] Conventionally, Al-9i was used as a material for automobile parts.
Extruded materials of eutectic and superalloys have been used, but recently continuous cast rods have come into widespread use.

This continuously cast rod has the effect that crystallized substances are made finer and its strength is improved due to the increase in solidification rate as the diameter is reduced.

However, when the solidification rate is increased in a half-plane Al-8r alloy, the ingot structure becomes a structure having twin planes called a feather structure. This feather structure causes a problem in that it causes cracks in the forging process, which is the cutting process.

[Problems to be Solved by the Invention] As explained in Section 2, the present invention is based on continuous casting rods as a result of intensive research conducted by the present inventor in view of the problems of conventional continuously cast rods as automobile parts materials. By eliminating the feather structure of the rod and making the crystal grains into equal parts, it has high strength and excellent wear resistance, and does not crack when sheared.It also contains Sr and Na. By doing so, they found that the content of B could be reduced, and that the eutectic Si could be granulated and the primary Si crystals made finer. Based on this knowledge, they developed a high-strength, wear-resistant continuous cast aluminum alloy material. .

[Means for Solving the Problems] The high-strength, wear-resistant continuous cast aluminum alloy material according to the present invention is characterized by: Si 7.5 to +3.5 wt%, Cu 3.0 to 6.
OwL%, Mg 0.3-1. owt%, Fe 0. ，
2-0.5vt%, Mn 0.2-0.5vt%, I3
Contains 0.002 to 0.03 wt%, S r 0.003 to 0.015 wt%, Na 0.0
0.03 to 0.015 wt% of HL-containing HL, and the remainder is AI and impurities.

Note that the size of crystallized particles in the high-strength, wear-resistant continuous cast aluminum alloy material according to the present invention is preferably 30 μm or less.

The high-strength, wear-resistant continuous cast aluminum alloy material according to the present invention will be described in detail below.

First, the components and Fr content of the high-strength, wear-resistant continuous cast aluminum alloy material according to the present invention will be explained.

Si is an essential element for imparting wear resistance.
If the content is less than 7.5 wt%, this effect will be small, and if the content exceeds 13.5 wt%, a large amount of primary Si will be generated, which will deteriorate the forgeability and mechanical properties, especially toughness and fatigue strength. Getting worse. Therefore, the Si content is 7.5 to 13,
It is set to 5wt%.

Cu is an element that improves mechanical properties, prevents seizure, and improves wear resistance, and the content is 3.0wt5
If the content is less than 6.0 wt%, this effect will be small, and if the content exceeds 6.0 wt%, forgeability will be inhibited. Therefore, the Cu-containing M content is set to 3.0 to 6.0 wt%.

Mg is an element that not only improves mechanical properties but also forms MgtS+ precipitates and imparts wear resistance. If the content is less than 0.3 wt%, this effect is small;
If the rH content exceeds 0 wt%, forgeability will be inhibited. Therefore, the Mg-containing fTffi is set to 0.3 to 1.0 wt% within a range that does not inhibit forgeability.

Pc and Mn exhibit almost similar effects, that is, they promote the formation of fine crystalline Si and Si-based precipitates, and also promote the formation of 51-
It is an element that improves wear resistance by forming Mn-Fe-based products, and if the content is less than 0.2 wt%, this effect will be small, and if the content exceeds 0.5 wt%, it will not be effective. and generates giant compounds that deteriorate forgeability and mechanical properties.

Therefore, the Fc content and Mn-containing a bond are 02~0.5w
It is assumed to be t%.

B is an element that has the effect of making the ingot structure into fine uniform parts, eliminating the feather structure, eliminating cracks caused by feathers during yarn cutting, and stabilizing the strength,
If the am content is less than 0.002 wt%, such an effect will be small, and if the am content exceeds 0.03 wt%, the effect will be saturated. Therefore, I3-containing (Mful; k 0
．． 002-0.03 wt% and -J-le.

Sr and Na are elements that have the hli auxiliary dynamic effect of crystal grain refinement, and have the effect of refining crystalline Si, and their content is 0.
．． This effect is small below 0.003wL%, and Q,
If the content exceeds 0.015 wt%, this effect will be saturated. Therefore, the Sr content is 0. OQ3~0.012
~0.5wt%, Na content is 0.003~0.015
Let it be wt%. Note that since 5rSNa exhibits similar effects, it is sufficient to contain any one of them. -For boat fishing, it is best to select a type based on the time until casting.

In addition, in the high-strength, wear-resistant continuous cast aluminum alloy material according to the present invention, the size of crystallized particles is 30 μm or less, thereby eliminating cracks during shear cutting.
Can provide high strength and wear resistance.

[Example 4] Next, a high-strength, wear-resistant aluminum ram alloy continuous casting according to the present invention (Example 4) will be described.

Example 1 Items No. 1-No. 6 shown in Table 1 are high-strength, wear-resistant continuous cast aluminum alloy materials according to the present invention.

At the time of melting, selectively adding elements Na and Sr, the initial product,
J! Aiming to make the microcrystalline silicon finer and increasing the cooling rate to 10°C
It was continuously cast into a round bar with a diameter of 32 mm at a rate of 1/sec or more, and the crystallized material was made finer.

No. 1 of the high-strength, wear-resistant aluminum alloy continuous casting material according to the present invention manufactured in this manner.

A microscopic photograph of the metal structure of No. 2 is shown in FIG. As shown in FIG. 1, all of the crystallized substances have been refined to 10 μm or less.

As a comparative example, No. 8 in Table 1 shows high strength according to the present invention.
Wear-resistant aluminum alloy continuous casting material No.

2, but it does not contain Sr, so A'
A microscopic photograph of the metal structure of No. 8 is shown in FIG. 2, and it can be seen that the structure of the product is important.

Figures 3, 4, and 5 are Nos., 2, No. 3 of high-strength, wear-resistant aluminum alloy continuous casting +4 according to the present invention.
and a micrograph of the metal structure of the ingot of Comparative Example No. 7.

Figure 3 shows fine equiaxed crystals, and Figure 4 shows equiaxed crystals in the center of the ingot and columnar crystals in the outer periphery.
No feather tissue.

Moreover, FIG. 5 shows a feather structure.

No. 1 to No. G of the high-strength, wear-resistant aluminum alloy continuous casting material according to the present invention shown in Table 1 and N of the comparative example
Table 1 shows a comparison of the characteristics of Nos. o, 7 to No., and ll.

For wear resistance, two T6 treated materials were tested using an ultra-thin type abrasion tester at a friction speed of 1.0 m/sec and a load of 2.1 kg, and the specific wear amount was compared.

Tensile strength and mechanical strength were tested using two T6 treated materials.

As is clear from Table 1, the high-strength, wear-resistant aluminum alloy continuous casting material according to the present invention is Comparative Example No. 1.
It has higher strength than the A4032 alloy of No. 0 and excellent wear resistance, and also has higher strength than the A390 alloy of Comparative Example No. 11.

In each of the alloys shown in Table 1, cracks are more likely to occur during cutting due to hardness, so the cuttability was evaluated by varying the hardness of the alloy.

The evaluations shown in Table 1 are as follows.

(q): IIRB 50-55 no time lag ○:
Hl<84 (No time cracking between 1 and less than 50 tl ln1
3 Cracks occurred in some parts with 50 or more △: llR830~
No cracking occurs when less than 40 1-11111 Cracking occurs in some areas at 40 or more The evaluation is ○~ri0),
The cutting properties are excellent compared to Comparative Examples No. 7, No. 8, and Comparative Examples No. 7, No. 8.

[Effects of the Invention] As explained below, the high-strength, wear-resistant continuous cast aluminum alloy material according to the present invention has the above-mentioned configuration.
It has high strength and excellent wear resistance, as well as excellent cuttability.

[Brief explanation of the drawing]

FIG. 1 is a micrograph showing the metal structure (microstructure w,) of No. 2 in Table 1 of the high-strength, wear-resistant aluminum alloy continuous caster 4 according to the present invention, and FIG. 2 is a comparative example No. Fig. 3 is a micrograph showing the metallographic structure of No. 7 (Miku (J structure)); (macrostructure); Figure 4 is a micrograph of the metal structure (macrostructure) of ingot No. 3; Figure 5 is comparative example No.
It is a micrograph of the metal structure (macrostructure) of No. 97 ingot. Ward,'1 Sujikuzu Hōjiga 1 Figure 2 Procedural Amendment (Method) March 23, 1988 Mr. Kunio Ogawa, Commissioner of the Patent Office ■ε■,
ε-ness. Indication Patent Application No. 311556 of 1988 2 Name of the invention High-strength, wear-resistant aluminum alloy continuous casting material 3 Relationship with the person making the amendment Case Patent applicant address 1-3-18 Wakihama-cho, Chuo-ku, Kobe City Issue name (l
9) Kobe Steel Co., Ltd. Fujiwa Toyocho Co-op No. 901 5. Date of amendment order: February 23, 1988 (dispatch mill) 6. Subject of amendment Figure 1, Figure 2, Figure 3, Figure 4. Figure, Figure 5. 7. Details of the amendment as shown in the attached sheet.

Claims (2)

[Claims] (1) Si7.5-13.5wt%, Cu3.0-6.
0wt%, Mg0.3-1.0wt%, Fe0.2-0
．． 5wt%, Mn0.2-0.5wt%, B0.002
~0.03wt%, and one selected from Sr0.003~0.015wt% and Na0.003~0.015wt%, with the remainder consisting of Al and impurities. Continuously cast aluminum alloy with high strength and wear resistance. (2) The high-strength, wear-resistant continuous cast aluminum alloy material according to claims 1 and 2, characterized in that the size of crystallized particles is 30 μm or less.