JPS6267133A - Production of fiber reinforced metallic member - Google Patents

Abstract

PURPOSE:To produce a high strength fiber reinforced metallic member with high fillability by compacting short fibers of ceramics to form a preform and by surely filling a molten metal into the preform. CONSTITUTION:In the 1st stage, short fibers or whiskers of ceramics are compacted to form a preform. In the 2nd stage, the preform is immersed in a soln. contg. metallic powder which is readily oxidized to generate heat and a binder to impregnate the soln. into the surface layer of the preform. In the 3rd stage, the preform contg. the impregnated soln. is preheated in a nonoxidizing atmosphere in a preheating furnace. In the 3rd stage, the preform contg. the impregnated soln. is preheated in a nonoxidizing atmosphere in a preheating furnace. In the 4th stage, the preheated preform is taken out of the furnace and put in the air, where the metallic powder present in the preform is oxidized to generate heat and a molten metal is rapidly filled into the preform to obtain a fiber reinforced metallic member.

Description

[Detailed Description of the Invention] Riouyu! Field IU11 The present invention relates to a method for manufacturing a fiber-reinforced metal member, and particularly to a method for manufacturing a fiber-reinforced metal member.
The present invention relates to a manufacturing method that can reliably perform filling.

"Komekani IIH reinforced metal material (FRH) is a material in which reinforcing fibers are interposed in a matrix metal, and the reinforced t/a
As II, non-metallic material 18N, in which metals, intermetallic compounds, oxides, nitrides, carbides, and other non-metallic materials are used, has a strength and an elastic modulus that is large compared to its density. It is superior to metal-based IIN because it reacts with the matrix metal less and dissolves less, and its strength decreases less at high temperatures.

In addition, in the production of fiber-reinforced metal members by the molten metal infiltration method, reinforcing fibers (short IJAH1 or whiskers)
In most fiber-metal combinations, wettability with the molten matrix metal has to be taken into consideration.For example, pressure casting, vacuum casting, etc. Molten metal is forcibly infiltrated between 11 and 11 by a casting method.

In this method, the Il fiber molded body used as the reinforcing fiber is preheated to promote penetration of the molten metal, but the fiber molded body taken out from the preheating furnace is placed in a composite casting mold. By the time stagnation begins, the temperature of the fibrous molded body has dropped, and the temperature drop in its surface layer is particularly significant, so that the temperature of the fibrous molded body at the time of stagnation is below the solidus line of the matrix metal. (In the part A, the matrix metal solidifies during composite casting, leading to deterioration of filling properties. 4-46゜Such a phenomenon occurs in the case of A1 alloy. Mg has a smaller latent heat of fusion and solidifies quickly compared to Mg.
This is especially likely to occur in alloys, and it is difficult to manufacture a sound composite member with a strength of 6+111.

An object of the present invention is to reliably fill a fiber molded body with molten metal in the production of a cord-reinforced metal member, thereby eliminating defects. The goal is to obtain a reinforced metal member with a strong binding cord.

The purpose of this is to shrink and mold ceramic 11H4rI'E (first step) so that it does not turn into an Il miscellaneous compact (first step), mix it with a metal powder that easily oxidizes and generates heat, and a binder and immerse it in a solution. Impregnating at least the surface layer of the l1lff molded body with the solution (third step), preheating the fiber molded body impregnated with the solution in a preheating furnace in a non-oxidizing atmosphere (third step), and removing the fiber molded body from the preheating furnace. This is achieved by taking out the metal powder contained therein, oxidizing and generating heat, and quickly filling the fiber molded body with molten metal (fourth step).

In the present invention, in order to suppress the temperature drop of the IN molded body taken out from the preheating furnace, a metal powder that is easily oxidized and generates heat is contained in the fiber molded body prior to preheating, and the fiber molded body is preheated. It utilizes the oxidation and heat generation of the metal powder that occurs when it is taken out of the furnace, and the metal powder includes Ti powder, Ti powder,
Zr powder and Fe powder are preferably used. This metal powder is mixed with a binder (eg, acrylic resin) in a solvent (eg, acetone), and is incorporated into the fibrous molded body by immersing the fibrous molded body in the mixed solution. The IJAN molded body immersed in the solution is pulled out and then heated and dried, but the metal powder is fixed to the fibers H@ by the binder and prevented from detaching from the ilH molded body.

According to the method of the present invention, various structural members of stable quality and high strength, such as rocker arms for internal combustion engines, connecting rods, and pistons, can be obtained.

The smaller the particle size of the metal powder used, the more likely it is to oxidize and generate heat at low temperatures, so it is appropriate to use a metal powder with a diameter of 50 μm or less, and especially if it is set to a diameter of 10 μm or less, it will not penetrate into the fiber molded product. Since it is easy to enter, good binding can be obtained.

Mouse 11”- ■By compression molding S^C whiskers, the linear layer volume fraction (V
f) = 18% fiber molded body was created.

■ Acrylic resin with hardening agent (product name,
1 tJ of solution prepared by dissolving 25111% of Olipain)
Solution 11 was prepared by adding and mixing 100 or of Ti powder with a particle size of less than 10 μm and T with a particle size of 42 to 44 μm.
A solution (2) in which 100 gr of I powder was added and mixed was prepared.

■The fiber molded body obtained in item (■) itself was designated as Comparative Example Test Piece A, and the fiber molded body immersed in solution (■) was designated as present invention side test piece B, and the untreated mH molded body was immersed in solution (■). This was designated as test piece C of the present invention.

■Test piece A was placed in a preheating furnace at a temperature of 700°C in an air atmosphere.

C was charged, and after the temperature reached 700° C., it was taken out of the furnace and allowed to cool in the atmosphere, and the temperature changes during that time were measured separately and are shown in FIG.

■Test piece B taken out from solutions T and II, respectively.

C and test piece A were placed in an argon gas atmosphere at a temperature of 700.
℃ preheating furnace, and after the temperature reached 700℃, they were taken out of the furnace and left to cool in the atmosphere, and the temperature changes during that time were measured individually, and the results are shown in Figure 2. In addition, FIG. 3 shows the relationship between the elapsed time and the temperature after each test piece A, B, and C was taken out of the preheating furnace.

<Evaluation> ■Regarding Figure 1: When heated in air, test piece C (
Containing Tλ powder with a particle size of 42 to 44 μm), the test piece Δ(
The tare temperature rate is higher than that of sweets containing Tλ powder, and 7
The heating time to reach 00° C. was approximately 172 times longer for Test C than for the test piece. Further, when the test piece C was taken out of the furnace, a slight temperature -ha was observed. It is clear that both river edges are caused by oxidation and heat generation of the Tλ powder.

■Regarding Figures 2 and 3: 700℃ in argon gas
When test piece B (containing T2 powder with a particle size of less than 10 μm) and test piece C that had been heated to a temperature of 100 μm were taken out, a temperature fluctuation that was not observed in the test pieces was observed.

In addition, the casting speed after taking out of the furnace decreases in the order of test piece A>test piece C>test piece B, and after 1 minute from the start of cooling, the drop rate of each test piece is as follows. Met.

Test piece A: 316°C Test piece B: 188°C Test piece C: 220°C From these results, the cooling rate of the IBM compact without Tx powder treatment is much larger than that of a fiber molded body treated with T-powder, whereas when the same T is treated with powder, the smaller the particle size of the Ti powder used, the lower the cooling rate, and the lower the temperature drop rate. It turns out that a great effect can be obtained.

Normally, the fiber molded body is taken out from the preheating furnace, set in a mold, and takes about 3 to 30 minutes to start composite casting.
According to Figure 3, during that time, test piece A's temperature drops by about 150 to 240 degrees Celsius, and test piece B's temperature drops by about 10 degrees Celsius.
~100°C temperature drop.

As shown above, the effect of not using Ti powder has been confirmed, and it can be seen that sound composite casting can be performed by the present invention.

Three rod-shaped mH molded bodies were obtained by molding W12 SλC whiskers. Each fiber molded body was subjected to powder treatment (powder particle size: 44 μm) with the same T as in Test Example 1, and charged separately into a preheating furnace in an argon gas atmosphere.
After heating to ℃, it was taken out of the furnace and left to cool.During that time, the moisture content was measured using a thermocouple attached to the outer peripheral surface of each fiber molded body, and the state of temperature change was measured as shown in Figures 4 to 6. Shown in the figure.

According to Fig. 6, when a fiber molded body is heated at 800°C for 15 minutes and then taken out of the furnace, the aging of the outer peripheral surface is approximately 1.
The temperature reaches 150°C, and the oxidation and heat generation of the Ti powder is effectively carried out.In addition, in the 111N compacts heated to 600°C and 700°C and taken out of the furnace, there is less direct oxidation and T
It can be seen that the oxidation and heat generation of the powder is insufficient.

Note that FIGS. 7 to 9 are shown for comparison with FIGS. 4 to 6, respectively, and three rod-shaped fiber cord molded bodies made of SzC whiskers, which are not subjected to Ti powder treatment, are shown in each case. Separately, the samples were placed in a preheating furnace in an argon gas atmosphere and heated to 600°C, 700'C, and 800°C, respectively, and then taken out of the furnace and left to cool.

From the comparison of each figure, it is possible to clearly understand the effect of applying Ti powder treatment, and according to the present invention, the I! It is possible to maintain the temperature of the fiber molded body at a certain level, thereby achieving sound composite casting.

Example 1 - A sea molded body formed by compression molding SλC whiskers was subjected to a treatment similar to the Ti powder treatment in Test Example 1, and then heated in an argon gas atmosphere in a preheating furnace at a set temperature of 800°C. The fiber molded body that reached the target temperature (800°C) was taken out of the furnace, and the fiber molded body whose temperature rose due to oxidation of the Ti powder and heat generation was immediately placed in a casting mold heated to 300°C. Under the oxidation and exothermic conditions of Tλ powder,
MCI alloy (AST
The molten metal (HAS41 material) was filled into a fiber molded body at a pressure of 1000/(g/cd), and allowed to cool and solidify.

There were no defects in the obtained fiber-reinforced metal member.

Class-1 ■ When using Ti powder: Since the oxidation and exothermic temperature of Ti powder is 700 to 800°C, the preheating temperature of the fiber compact containing Ti powder should be set to 700°C or higher. be. In addition, the matrix metal to be composited is Al.
1 alloy, Mg alloy, etc., the temperature of the molten metal 1α is 700°C or higher, so in order to improve the filling properties of the matrix metal molten metal, preheating of the fiber molded body containing Ti powder is necessary. The temperature should be set at around 800°C.

■7r powder, [near r powder when using e powder, 1”e
The oxidation and exothermic temperature of the powder is about 400°C, but considering the filling properties of the molten matrix metal, the preheating temperature of the fiber molded body needs to be set to 600°C or higher.

As is clear from the above explanation, Zeramitsu fibers are compression-molded to form a fiber molded product (the first step), and this is mixed with a metal powder that easily oxidizes and generates heat and a binder. The fiber molded article is immersed in the solution to impregnate at least the surface layer of the fiber molded article with the solution. (Third step), preheating my molded body after solution impregnation in a preheating furnace in a non-oxidizing atmosphere; Third step), taking out the fiber molded body from the preheating furnace and oxidizing the metal powder contained therein; A method for manufacturing a fiber-reinforced metal member is provided, which is characterized by generating heat and quickly filling a molten metal into a molded body (fourth step).

According to this method, the I! Since the temperature of the fiber compact increases due to oxidation and heat generation of the Ti powder,
The cooling rate is delayed, and as a result, composite casting of matrix metal can be performed on fiber molded bodies at a higher temperature than before, and it is possible to perform composite casting of matrix metal, which may cause local solidification of matrix metal during the casting process. Therefore, a high-strength fiber-reinforced metal member with good filling properties and no defects can be obtained.

[Brief explanation of drawings]

Figure 1 shows a fiber molded body (test piece A) that does not contain Ti powder.
A graph showing the temperature change when an am molded body (test piece C) containing Tλ powder and Tλ powder is heated in a preheating furnace in an air atmosphere, then taken out of the furnace and left to cool. After heating the 1112 molded body containing Tλ powder (test piece A) and the 1112 molded body (test pieces B, C) containing Tλ powder in a preheating furnace in an argon gas atmosphere, they were taken out of the furnace and left to cool. The graph shown in Figure 3 is a graph showing the relationship between the elapsed time and the temperature drop after taking out the test pieces from the preheating furnace in the argon gas atmosphere for each of the above-mentioned test pieces, and Figures 4 to 6 are graphs showing the relationship between Ti powder A graph showing the temperature change when the fiber molded bodies containing the fibers are charged into preheating furnaces with set temperatures of 600°C, 700"C, and 800°C, heated, and then taken out of the furnace and left to cool. Figure 9 shows a fiber molded body containing no T^ powder at a set temperature of 600°C.
700℃. 1 is a graph showing the temperature change when each sample was charged into a preheating furnace at 800° C. and heated, then taken out of the furnace and allowed to cool.

Claims (5)

[Claims] (1) A first step of compression molding ceramic short fibers or ceramic whiskers to obtain a fibrous molded body, immersing the fibrous molded body in a solution containing a binder and a metal powder that easily oxidizes and generates heat; a second step of impregnating at least the surface layer of the fiber molded body with the solution; a third step of preheating the fiber molded body impregnated with the solution in a preheating furnace in a non-oxidizing atmosphere; The fourth step is to take out the metal powder in the atmosphere, oxidize and heat the metal powder present in the fiber molded body, and quickly fill the fiber molded body with molten metal. Production method. (2) The method for manufacturing a fiber-reinforced metal member according to claim 1, wherein the ceramic fibers are SiC fibers. (3) The method for manufacturing a fiber-reinforced metal member according to claim 1 or 2, wherein the molten metal is an Mg alloy. (4) The metal powder described in claim 1, 2, or 3 is characterized in that the metal powder is at least one selected from the group consisting of Ti powder, Zr powder, and Fe powder. A method for manufacturing a fiber-reinforced metal member. (5) Claims 1, 2, and 3, characterized in that the preheating temperature of the fiber molded body is 600°C or higher.
A method for producing a fiber-reinforced metal member according to item 4.