JPS59136404A - Preparation of super-hard anti-wear and impact resistant tool - Google Patents

Abstract

PURPOSE:To obtain even an elongated shape tool in good quality and yield, in a tool preparing method for sintering a hard metal stock powder after compression molding, by integrating separately molded and sintered regions by re-sintering. CONSTITUTION:For example, after hard metal stock powders different in material quality are respectively molded into desired shapes, the molded ones are preliminarily sintered and subjected to proper finish molding corresponding to a degree generating strain and final sintering to obtain members 10, 12. In the next step, the whole containing contact surfaces 14, 16 of the members 10, 12 are subjected to finish molding and the right angle degree of the surfaces 14, 16 are especially secured while an oxide film is sufficiently removed. Thereafter, re- sintering is performed in such a state that the contact surfaces of the members 10, 12 are closely contacted to obtain a super-hard anti-wear and impact resistant tool 18 wherein both members are integrally connected.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a carbide wear-resistant and impact-resistant tool, and more particularly to a method for manufacturing a carbide wear- and impact-resistant tool in which separately molded and sintered parts are integrated by resintering.

To manufacture carbide wear-resistant and impact-resistant tools, cemented carbide raw material powder is placed in a mold and compression molded. However, this powder has low fluidity, so it is difficult to manufacture carbide tools that are long in length relative to their diameter. In the case of manufacturing, etc., the pressure tends to be insufficiently distributed during compression molding, resulting in uneven pressure application, which tends to result in irregular shapes and cracks during sintering.

Therefore, it is extremely difficult to manufacture carbide tools, etc., which have a long length relative to their diameter, and are difficult to manufacture with good quality. There was a problem. This is true even when the cross section is a polygon other than circular, and when the length of the carbide tool is long.

In addition, since the strength required for carbide wear-resistant and shock-resistant tools such as parts formers differs depending on the part of the workpiece that is plastically worked during use, conventionally, for example, as shown in Figure 1, the strength required is high. A cemented carbide 2 having a high hardness and a cemented carbide 4 having a high toughness and low hardening are manufactured separately, and these are fitted into a case 6 and brought into contact with each other for use in combination.

However, the conventional means of simply bringing cemented carbide into contact with each other makes it difficult to connect the internal forming holes, and the workpiece is easily damaged in the form of a ring during plastic processing, or easily broken during use. There were other problems. In addition, the strength of the cemented carbide required for press punches, etc. differs between the tip and the part in contact with it, but in press punches, etc. used for punching holes, different types of cemented carbide are fitted into the case. is impossible.

The present invention was made against the background of the above, and an object of the present invention is to prevent irregular shapes even when manufacturing carbide tools having a long length relative to the diameter. , there is no cracking, the quality is good, and the product holds well, and there is no need to fit two or more different types of cemented carbide into the case. The object of the present invention is to provide a method for manufacturing a wear-resistant and impact-resistant tool that is integrally joined and blue in color.

The gist of the present invention, which has been made to achieve such an object, is to provide an F! In the A manufacturing method (ζ), after compression molding and sintering two or more parts separately, the joint surfaces of each sintered member are finished, and each finished surface is brought into close contact to form an IC-shaped 1 A method of manufacturing a carbide wear-resistant and impact-resistant tool is characterized in that the tool is re-sintered and integrated and then further molded and finished.

According to the present invention, each part divided into two or more parts is compression molded separately, so even if the length of a carbide tool is long relative to the diameter, the compression state of each part will not be uneven. Irregular shapes, cracks, etc. do not occur, and the quality of the cemented carbide tool can be improved and costs can be reduced. In addition, since the joint surfaces of each sintered member are finished and then joined, the joint surfaces adhere well and the oxide film etc. on the joint surface can be removed, so the joint strength of each member is increased by sintering. This increases the lifespan of the carbide tool. Also, since each part is molded and finished after sintering, the dimensional accuracy of the carbide tool itself can be improved, which in turn improves the quality of the product being machined. It becomes possible to increase the

Hereinafter, the present invention will be explained in detail based on the drawings.

The cemented carbide raw material powder to be used in the present invention is well known for use in manufacturing cemented carbide wear-resistant and impact-resistant tools, and an appropriate grade is selected depending on the required strength and the like.

In the present invention, each of the raw material powders selected in this way is press-molded using a mold according to a conventional method, and the obtained molded product in the desired shape is pre-sintered according to a conventional method. After finishing the molding, main sintering is performed, then the joint surfaces of each member obtained by main sintering are finished, and then re-sintering is performed with the finished joint surfaces in close contact, A carbide wear-resistant and impact-resistant tool is obtained by sintering each member together and then forming and finishing it into desired dimensions. Press forming is performed by corporating raw material powder into a shape, for example, into a ring shape as shown in Figure 2 A. However, in Figure 2 A, for example, cemented carbide metal-containing materials are used as the raw material powder according to the usage classification. Use a material equivalent to J■SV5, and use a material equivalent to the same Jrsv6 for the mouth of the same figure, and use
Pressure is applied at a pressure of 500 kg/item to obtain a molded product. The molded product formed into the desired shape is then heated to, for example, 600 to 900°C.
A sintering process is performed for about 0.5 to 1.5 hours at a temperature of about 1,400 degrees Celsius.
Part 10.1 is subjected to firing treatment for about 2 hours, so-called main sintering.
Get 2. The member 10.12 then joins the joint surface 11! I,
The entire body including 16 is molded and finished, but especially the joint surface 14
．． This is done to ensure a perpendicularity of 1'6 and to sufficiently remove the oxide film. Next, with the joint surfaces of the members 10 and 12 in close contact, a firing process, so-called re-sintering, is performed at a temperature of, for example, 1400°C for about 1 to 2 hours.
A carbide wear-resistant and impact-resistant tool (not shown in FIG. 3) in which both members are integrally joined can be obtained.

In addition, as shown in FIGS. 4 and 5, members 20 and 22 made of cemented carbide having the same grade symbol obtained through the steps of press forming, preliminary sintering, and main sintering were also prepared in the same manner as above. It is also possible to obtain a cemented carbide tool 24 which is long in length relative to its diameter by joining together and resintering.

Furthermore, as shown in FIGS. 6 and 7, members 26 and 28 made of cemented carbide obtained in the same manner as described above are joined together in the forward orientation to form a superstructure with a large diameter and a long length. Hard alloy 30@
It is also possible to obtain

As detailed above, according to the present invention, two or more parts are compression molded separately, so even if the carbide tool is long in length relative to its diameter, each part can be molded uniformly. It is possible to prevent irregular shapes, cracks, etc. In addition, the parts that are molded and sintered for each part are joined after the joining surfaces are finished, so they stick together and sinter, increasing the joining strength and extending the life of the carbide tool. . In addition, each part is formed after sintering and E-bent, making it possible to maintain the dimensional accuracy of each part, ensuring a dimensional range that has the toughness, wear resistance, etc. required for each part. Therefore, breakage of the cemented carbide tool can be prevented and its durable life can be increased. Furthermore, since the molding and finishing are performed after the integral construction by re-sintering, there are no difficult differences in the seams between the parts, which in turn prevents scratches on the processed product, improving its quality. It is possible to make it "direct".

Next, the present invention will be further explained by examples! As will be explained in (2), the present invention is not limited to the examples unless it goes beyond the gist thereof.

Example ■ Fig. 2 A, Cemented carbide member (A: Grade JI)
Equivalent to SV5, outer diameter D1=60mm, hole diameter d1=23.9
5+nm, length 11=60mm, B: U type JiSV6
Equivalent, outer diameter D2 = 60111t11 hole diameter d2 = 23, 9
5mm, d a = 21.79 + 11m, b = 5.
0 mm, length vertical 2 = 110 mm) was obtained in accordance with a conventional method, and then the whole was ground and finished paying particular attention to the joint surfaces, and then the two members were ground at a temperature of 1370°C with the two members in close contact.
By resintering for a time, a W carbide wear-resistant and impact-resistant tool (shown in FIG. 3) was manufactured. This cemented carbide tool is made of hardened alloy members 10 of different grades.
．． 12, but both were strongly sintered together.

In this example, it is possible to use the workpiece even after processing approximately 150,000 pieces, but the conventional example in which each cemented carbide member is inserted into the case will break after approximately 100,000 pieces are used. Couldn't use it.

■ Fig. 4 A, Cemented carbide member shown at the mouth (A: Outer diameter -5
0mm, Length -9Qn+n+, B: Outer diameter -5Qmm.

Length 195m+n, Δ species...A, mouth J l5V
6) was obtained according to a conventional method, and then a carbide wear-resistant and impact-resistant tool having a longer length than the diameter shown in FIG. 5 was manufactured in the same manner as in the case ① above. The part A and the part mouth were firmly and tightly joined.

■ Figure 6 A, Cemented carbide member not shown (A: Grade J
Equivalent to l5V5, outer diameter Db=80mm, outer diameter, 7-65
mm, length i, = 1i omm, length 7-1
01, Oz grade equivalent to JISV5, outer diameter ()g=65mm
, outer diameter Dq = 50mm, length fJ-9 = 110m
m, length q-5011IIIl) is obtained according to the usual method,
Next, in the same manner as in the case (2) above, a carbide wear-resistant and impact-resistant tool having a large diameter and long length as shown in FIG. 7 was manufactured.

The part A and the part mouth were firmly and closely joined.

Furthermore, long and thick carbide tools require a mold with special molding features, and also require a tall heat treatment furnace for heat treatment, which is difficult to manufacture and extremely costly. In this example, it is easy to manufacture and the cost can be reduced compared to the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a carbide wear-resistant and impact-resistant tool constructed by fitting two types of cemented carbide members into a case, and FIG. FIG. 3 is a cross-sectional view of each member of the cemented carbide manufactured according to the method, and FIG. 3 is a cross-sectional view of a cemented carbide, wear-resistant wIi hammer tool constructed by integrally sintering the respective members. Figure 4A is a cross-sectional view of each cemented carbide member constituting a cemented carbide tool according to another embodiment of the present invention, and Figure 5 is a cross-sectional view of each member made of cemented carbide that constitutes a cemented carbide tool according to another embodiment of the present invention. It is a sectional view of a cemented carbide tool. Figure 6A is a cross-sectional view of each cemented carbide member constituting a cemented carbide tool according to yet another embodiment of the present invention, and Figure 7 is a cross-sectional view of each member made of cemented carbide that constitutes a cemented carbide tool according to another embodiment of the present invention, and Figure 7 shows a cross-sectional view of each member made of cemented carbide that is sintered together. It is a sectional view of a cemented carbide tool. 10.12.20, 22.26.28... Member 14.
16... Joint surface 18.24.30... Carbide tool Fig. 1 6 (a) (b) Fig. 5 20 22 Fig. 6 6 Fig. 7 0

Claims (1)

[Claims] 1. In a method for manufacturing a cemented carbide wear-resistant and impact-resistant tool in which predetermined cemented carbide raw material powder is compression-molded and then sintered, two or more parts are compression-molded and sintered separately, and each of the sintered members is A method for manufacturing a carbide wear-resistant and impact-resistant tool, which comprises finishing the joint surfaces of the tools, re-sintering the finished surfaces in a state in which they are in close contact with each other, and then forming and finishing the tool.