JP2000042756A - Wear resistant liner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve joinability between a sintered hard alloy and a steel base stock in using a sintered carbide excellent in wear resistance as a wear resistant liner. SOLUTION: In this wear resistant liner obtained by laminating a sintered carbided plate 1 of 1-25 mm thickness with a steel plate 2 by solid phase diffusion welding, at the boundary between the sintered carbite 1 and the steel plate 2, a copper 3 is arranged on a sintered carbide side and Ni is arranged on a steel plate side, and an oxygen-free copper is used for the copper plate 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an abrasion-resistant liner used in a place where a material such as raw materials, earth and sand, ore, and the like, which are conveyed, crushed, and crushed, are subjected to wear.

[0002]

2. Description of the Related Art In the above-mentioned fields where excellent wear resistance is required, high Cr cast iron is used as a typical wear-resistant material instead of steel members.

However, for structural use, not only wear resistance but also strength and toughness are required. However, the wear resistance, strength, and toughness of materials generally tend to trade off, and the addition of carbon and other alloying elements to improve the wear resistance of high Cr cast iron significantly reduces strength and toughness.

[0004] Other wear-resistant materials include a welding plate in which a high Cr cast iron-based material is welded on steel, and a hard material such as cemented carbide or ceramics on the surface of a steel sheet by a mechanical method, bonding or brazing. There is a composite plate attached. In these composite plates, strength and toughness are provided by steel as a base material, and wear resistance is provided solely by a hard surface material.

However, problems remain with the use of such composite plates. In other words, the wear resistance improves with the amount of carbide in the high Cr cast iron-based weld metal,
On the other hand, the strength and toughness are reduced, and a large number of cracks are generated by welding residual stress, which causes a great risk that the hardened layer easily falls off in a short period of time in response to an impact during use.

When a cemented carbide or ceramics is applied to the surface of a steel sheet by a mechanical method, bonding or brazing, the bonding strength between the hard material and the steel sheet is weak. The material may fall off easily in a short time.

Table 1 shows the results of sand wear tests of various structural materials, and Table 2 shows the wear resistance ratios.

[0008]

[Table 1]

[Table 2] In the same table, each composition is as follows in weight%.

Weld liner C: 4.89, Si: 1.15, Mn: 0.35, Cr: 21.22, Nb: 3.16 Steel (S45C) C: 0.44, Si: 0.23 Mn: 0.62 cemented carbide C: 6.71, Co: 6.71, W: 82.9, Fe: 3.59, Si: 1.10, Cr: 0.91 Copper Cu: 99.9 or more High Cr cast iron C: 3.48, Si: 0.67, Mn: 0.62, P: 0.029, S: 0.014, Cr: 16.07 Ni: 1.20, Mo: 2.99 As is clear from the table, from the point of abrasion resistance,
The cemented carbide itself has very good properties.

[0010] However, since cemented carbide is unstable in bonding with steel, it is impossible to completely bond it over a large area by brazing. Therefore, even if an insert is used to increase the stability of the joint, the carbide part may fall off depending on the operating conditions, in which case the remaining steel will wear out in a short period of time. If they are found, urgent replacement is required, causing a large loss in maintenance work.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to improve the bondability between a cemented carbide and a steel base material when using a cemented carbide having excellent wear resistance as a wear-resistant liner. Is to do.

[0012]

The present invention has solved the problem by laminating a cemented carbide plate and a steel plate by solid phase diffusion bonding. The thickness of the cemented carbide plate is suitably from 1 to 25 mm for the following reason. The thickness of this type of liner can vary widely, from 12 to 100 mm, but is usually replaced when half of the initial thickness has worn out, T / 2 of half the total thickness T. The life can be prolonged reliably by replacing with a cemented carbide. However, since the cemented carbide has a large specific gravity, it is necessary to have a thickness of T / 4 or less to make the same weight as other parts of the liner. On the other hand, the wear resistance of cemented carbide is excellent,
It is sufficient if the thickness is 1/6 or more of T / 2 (T / 12 or more). For this reason, the thickness of the cemented carbide is set to 1 to 25 mm.

[0013] At the joint surface between the cemented carbide plate and the steel plate, a copper thin plate can be joined to the cemented carbide side and a Ni foil can be joined to the steel plate side. The purpose of inserting the Ni foil on the steel plate side is to prevent a decrease in bonding strength at the interface due to mutual diffusion of Cu and Fe that occurs when the copper plate and the steel plate are directly bonded. Further, as the copper plate, it is preferable to use oxygen-free copper capable of obtaining a higher joint tensile strength than deoxidized copper or tough pitch copper.

Regarding the conditions for the solid phase diffusion bonding, it is advantageous from the viewpoint of the bonding quality that the atmosphere is performed under a vacuum or an inert gas. The processing temperature is set for cemented carbide and steel,
As shown in Table 3 of the joint tensile strength data when copper is used as the insert metal for joining, it is known that sufficient strength can be obtained in the range of 900 to 1000 ° C. Also, joint strength can be further improved by inserting a Ni foil between copper and steel. Therefore, the processing temperature is 900 to 1
000 ° C is suitable.

[0015]

[Table 3] The test piece of cemented carbide / copper / steel is a cemented carbide made of WC-Co: thickness 5 mm × 10 mm × 10 mm, oxygen-free copper plate: thickness 2 mm × 10 mm × 10 mm, steel: section 10 m
It is a prism material of mx 10 mm.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below based on examples.

[0017]

EXAMPLE 1 As shown in FIG. 1, a cemented carbide plate made of WC-Co (thickness: 4 mm) was used.
mm × 100mm × 60mm) 1 into a steel plate (thickness 6mm ×
240 mm × 500 mm) 2 to produce a laminated wear-resistant plate. Between the cemented carbide plate 1 and the steel plate 2, a 1 mm thick oxygen-free copper plate 3 and a steel plate 2
Insert Ni foil 4 having a thickness of 10 μm on the side, and use a vacuum hot press device at 930 ° C. × 1.5 hr × 10 MPa
Bonding was performed under the following conditions. As for the joining results, no cracks and other results were observed in the cemented carbide, and inspection by an ultrasonic flaw detection test confirmed that the joining was complete. Example 2 As shown in FIG. 2, a cemented carbide plate (5 mm × 45 mm thick)
× 45mm) 1 and steel plate (thickness 10mm × 45mm × 45)
mm) 2 was manufactured. An oxygen-free copper plate 3 having a thickness of 0.3 mm is provided between the cemented carbide plate 1 and the steel plate 2.
And 900 ° C using a vacuum hot press
Bonding was performed under the conditions of × 0.5 hr × 10 MPa. The joining results were good, and no cracks or other defects were observed in the cemented carbide.

Example 3 A cemented carbide plate (thickness 5 mm × 4
5mm × 45mm) 1 to steel plate (10mm × 45mm thick)
× 45 mm) 2 to produce laminated wear-resistant parts. 0.5 mm thick between cemented carbide plate 1 and steel plate 2
Was joined by using a vacuum hot press device under the conditions of 950 ° C. × 0.5 hr × 10 MPa. The joining results were good, and no cracks or other defects were observed in the cemented carbide.

[0019]

According to the present invention, the characteristics of cemented carbide as a wear-resistant material can be utilized to the fullest extent in industry. In other words, by using steel as the base material, it can be easily attached to existing members or equipment by arc welding, and furthermore, it can be used as a component of any size by joining the base materials together by arc welding. It will be possible and the range of use will be widened.

In addition, since there is no need to replace parts in a short cycle in equipment maintenance, the cost associated with replacement is greatly reduced, and material costs are also reduced over the long term.

Further, by grasping the condition of wear of the cemented carbide part in daily inspection, it is possible to know in advance the next replacement time, so that it is possible to eliminate the loss of staffing due to emergency maintenance. Becomes

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory view showing another embodiment of the present invention.

[Explanation of Signs] 1: Cemented carbide 2: Steel plate 3: Copper plate 4: Ni plate

Claims (3)

[Claims] 1. A wear-resistant liner obtained by laminating a cemented carbide plate having a thickness of 1 to 25 mm and a steel plate by solid phase diffusion bonding. 2. The wear-resistant liner according to claim 1, wherein copper is provided on the cemented carbide side and Ni is provided on the steel side at the interface between the cemented carbide sheet and the steel sheet. 3. The copper plate according to claim 1, wherein the copper plate is made of oxygen-free copper.
The described wear-resistant liner.