CN102418040B

CN102418040B - Toothholder and manufacturing method thereof

Info

Publication number: CN102418040B
Application number: CN 201110369602
Authority: CN
Inventors: 钱嘉镕新
Original assignee: NINGBO JIADA PRECISION CASTING CO Ltd
Current assignee: NINGBO JIADA PRECISION CASTING CO Ltd
Priority date: 2011-11-13
Filing date: 2011-11-13
Publication date: 2013-06-05
Anticipated expiration: 2031-11-13
Also published as: CN102418040A

Abstract

The invention discloses a toothholder and a manufacturing method thereof, and is used for solving the problem that the traditional toothholder has poor mechanical property and welding property. The toothholder disclosed by the invention comprises the following components by mass percent: 0.19-0.22% of C, 0.80-1.10% of Mn, 0.30-0.60% of Si, 0.30-0.60% of Cr, 0.02-0.06% of Al and the balance of Fe and inevitable impurities. The invention also provides a manufacturing method for manufacturing the toothholder; and the manufacturing method comprises a founding process and a heat treatment process. By adopting the manufacturing method provided by the invention, the mechanical property of the toothholder is greatly improved, and the welding property of the toothholder can satisfy the toothholder demand.

Description

Toothholder and preparation method thereof

Technical field

The present invention relates to a kind of toothholder and preparation method thereof, relate in particular to a kind of excavator toothholder and preparation method thereof.

Background technology

The toothholder of excavator and crown consist of excavator bucket teeth.Connect by pin between toothholder and crown, it is the easy consumption parts of excavator.For extending excavator toothholder and crown life-span, reduce cost, the function different with crown according to toothholder, toothholder requires different mechanical propertys with crown.Wherein, crown is owing to directly contacting with ore, and it needs high rigidity, high-wearing feature and high strength and high tenacity.Toothholder requires good weldability, to guarantee the reliability of weld bond intensity and welding, guarantees simultaneously higher toughness and hardness.

The carbon content that the high strength of material and high tenacity are had relatively high expectations and alloy content, weldability needs to limit the content of carbon and alloy preferably, and existing material is difficult to find balance between both.

Summary of the invention

The objective of the invention is to have the problems referred to above for existing technology, proposed a kind of toothholder with good welds performance and mechanical property.

Purpose of the present invention can realize by following technical proposal: a kind of toothholder, the moiety of its special described toothholder and mass percent are: C:0.19%-0.22%, Mn:0.80%-1.10%, Si:0.30%-0.60%, Cr:0.30%-0.60%, Al:0.02%-0.06%, surplus is Fe and inevitable impurity.

Further, in described impurity, the mass percent of S element less than or equal to the mass percent of 0.035%, P element less than or equal to 0.035%.

Further, the moiety of described toothholder and mass percent are: C:0.20%, and Mn:1.0%, Si:0.4%, Cr:0.40%, Al:0.03%, surplus is Fe and inevitable impurity.

The present invention also provides a kind of preparation method of above-mentioned toothholder, comprises casting process and heat treatment step, in described heat treatment step, quenching temperature is 900 ℃, after quenching, soaking time is 2 to 4 hours, and tempering temperature is 220 ℃ to 250 ℃, and after tempering, soaking time is 2 to 4 hours.

Further, in described heat treatment step, tempering temperature is 230 ℃.

The present invention passes through the raw material of configuration specific components and mass percent, and obtains toothholder of the present invention by special thermal treatment process.Its good mechanical property, have high rigidity, high-tensile, high tenacity and good welding property, satisfy the special Working environment demand of excavator.

Embodiment

Embodiment one

In the present embodiment, the moiety of toothholder and mass percent are: C:0.19%, and Mn:0.80%, Si:0.3%, Cr:0.30%, Al:0.02%, surplus is Fe.Simultaneously, due to S, the P element detrimentally affect to the toothholder mechanical property, the mass percent that must guarantee the S element less than or equal to the mass percent of 0.035%, P element less than or equal to 0.035%.

The C element is as the fundamental element of steel alloy, and itself and Fe, Mn form carbide, improve hardness and the wear resistance of steel, have important solution strengthening effect.Therefore the carbon of high-content can directly improve hardness and the wear resistance of toothholder, but the C element is again the element that reduces welding property, and the present embodiment adopts the C element of 0.19% mass percent and coordinates other alloying elements can guarantee on the one hand that the welding property of toothholder guarantees again its mechanical property.

Although the Mn element is to promote austenite former in steel alloy, therefore the Mn constituent content is all higher usually, more than 10%.Yet, guaranteeing under the austenite structure prerequisite, reduction along with the Mn constituent content, although stabilization of austenite descends, but the workhardness ability significantly strengthens, and wear resistance significantly improves under the high impact effect, in this enforcement, Mn content is reduced to 0.80%, both guarantee austenite structure, and can significantly improve again the wear resistance of toothholder.

Add the Cr element can change carbide dispersion distributional pattern in steel in steel alloy, obtain with Cr ₂₃C ₆Be main granular carbide, its disperse is distributed on the Ovshinsky matrix.Add 0.30% Cr element can effectively improve the toothholder wear resisting property more than 2 times in the present embodiment.The Cr element can alleviate or avoid temper brittleness simultaneously, guarantees that the toothholder welded heat affecting zone still has higher toughness.

The Al element is mainly used in deoxidation and the outgassing in the alloy melting process, can cleaning molten steel.

The Si element is dissolved in ferrite, can strongly inhibited decompose with the carbide of alleviating supercooled austenite, improves stabilization of austenite, and its content coordinates with the Mn constituent content, can effectively improve the toughness of toothholder, improves intensity, yield ratio and the hardness of toothholder.

After determining the component and mass percent of toothholder, its preparation technology also has considerable influence to the mechanical property of the toothholder of final formation.The preparation technology of toothholder comprises casting process and heat treatment step, and wherein casting process adopts conventional casting get final product, and what the final mechanical property of toothholder was had the greatest impact is heat treatment step.Heat treatment step comprise quench to heat up, the step of air cooling after tempering after insulation, tempering.The present embodiment is for inquiring into optimum tempering temperature, to the thermal treatment and test its mechanical property under different tempering temperatures of toothholder in the present embodiment, obtains experimental result such as following table 1:

Table 1

As can be seen from the above table, tempering temperature is in 200 ℃ to 250 ℃ intervals, and tensile strength, hardness and normal temperature impelling strength all raise along with the rising of temperature, and reach maximum at 250 ℃.This is mainly that shear produces a large amount of oversaturated lath martensites because the tempering shear occurs in tempering between 200 ℃ to 250 ℃, microstructure is that dislocation and a large amount of dislocation are staggered, hinder Grain Boundary Sliding, produce the phase transformation strengthening effect, improve every mechanical property of toothholder.

And when tempering temperature during greater than 250 ℃, dislocation generation slippage and climbing causes dislocation desity to reduce, and crystal boundary is moved simultaneously, and subgrain merges and causes the every mechanical property of toothholder to descend.

Simultaneously, due to the mechanical property requirement of toothholder self, in selected the present embodiment, the heat treatment condition of toothholder is: be warming up to quench after 900 ℃ and be incubated 2-4 hour after tempering under the tempering temperature of 220 ℃ to 250 ℃, again be incubated 2-4 hour after tempering.

By the toothholder that obtains in the present embodiment, its mechanical property is good, satisfies the Working environment demand of excavator fully.

Embodiment two

In the present embodiment, the moiety of toothholder and mass percent are: C:0.20%, and Mn:1.0%, Si:0.4%, Cr:0.4%, Al:0.03%, surplus is Fe.Simultaneously, due to S, the P element detrimentally affect to the toothholder mechanical property, the mass percent that must guarantee the S element less than or equal to the mass percent of 0.035%, P element less than or equal to 0.035%.

In the present embodiment, toothholder is through casting process and heat treatment step, wherein heat treatment step adopts the processing condition the same with embodiment one, namely be warming up to quench after 900 ℃ and be incubated 2-4 hour after tempering under the tempering temperature of 220 ℃ to 250 ℃, again be incubated 2-4 hour after tempering.Test its mechanical property such as following table 2:

Table 2

After adopting the proportioning of the present embodiment, utilize its mechanical property of toothholder that the processing condition of embodiment one make still to satisfy excavator Working environment demand.

Embodiment three

In the present embodiment, the moiety of toothholder and mass percent are: C:0.22%, and Mn:1.10%, Si:0.60%, Cr:0.60%, Al:0.06%, surplus is Fe.Simultaneously, due to S, the P element detrimentally affect to the toothholder mechanical property, the mass percent that must guarantee the S element less than or equal to the mass percent of 0.045%, P element less than or equal to 0.045%.

In the present embodiment, toothholder is through casting process and heat treatment step, wherein heat treatment step adopts the processing condition the same with embodiment one, namely be warming up to quench after 900 ℃ and be incubated 2-4 hour after tempering under the tempering temperature of 220 ℃ to 250 ℃, again be incubated 2-4 hour after tempering.Test its mechanical property such as following table 3:

Table 3

Specific embodiment described herein is only to the explanation for example of the present invention's spirit.Those skilled in the art can make various modifications or replenish or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.

Claims

1. toothholder, it is characterized in that: the moiety of described toothholder and mass percent are: C:0.20%, Mn:1.0%, Si:0.4%, Cr:0.40%, Al:0.03%, surplus is Fe and inevitable impurity, in described impurity, the mass percent of S element is less than or equal to 0.035%, the mass percent of P element is less than or equal to 0.035%, the preparation method of described toothholder, comprise casting process and heat treatment step, in described heat treatment step, quenching temperature is 900 ℃, after quenching, soaking time is 2 to 4 hours, tempering temperature is 250 ℃, after tempering, soaking time is 2 to 4 hours.