阅读说明：本技术 一种内燃机轴瓦用白合金及其制备方法和应用 (White alloy for internal combustion engine bearing bush and preparation method and application thereof ) 是由 陈永红 钟宁 阳林 屠力月 罗才勇 辛琦 于 2020-11-30 设计创作，主要内容包括：本发明公开了一种内燃机轴瓦用白合金,按重量百分比计包括如下组分：3～4％的Cu,7～9％的Sb,0.18～0.3％的Ni,0.8～1.2％的Cd,余量为Sn以及不可避免的杂质。其综合力学性能优异,能够满足轴瓦的高承载力要求。还公开了上述内燃机轴瓦用白合金的制备方法,包括如下步骤：S1,按照上述组分的重量百分比称取铜镍中间合金、锑、镉和锡；S2,将称取的部分原料投入到熔炼炉中,升温至熔化温度并保温,使得熔炼炉内的混合材料完全熔化,然后加入余下的锡原料熔化并充分搅拌,将合金液温度降至420℃～450℃时加入镉,加入精炼剂进行精炼；S3,精炼完成后浇铸得到内燃机轴瓦用白合金。工艺流程简单,保证了各个元素在合金中均匀分布,提高了合金的力学性能。(The invention discloses a white alloy for a bearing bush of an internal combustion engine, which comprises the following components in percentage by weight: 3-4% of Cu, 7-9% of Sb, 0.18-0.3% of Ni, 0.8-1.2% of Cd, and the balance of Sn and inevitable impurities. The composite mechanical property is excellent, and the requirement of high bearing capacity of the bearing bush can be met. Also discloses a preparation method of the white alloy for the bearing bush of the internal combustion engine, which comprises the following steps: s1, weighing the copper-nickel intermediate alloy, antimony, cadmium and tin according to the weight percentage of the components; s2, putting part of the weighed raw materials into a smelting furnace, heating to the melting temperature and preserving heat to completely melt the mixed materials in the smelting furnace, then adding the rest tin raw materials for melting and fully stirring, adding cadmium when the temperature of the alloy liquid is reduced to 420-450 ℃, and adding a refining agent for refining; and S3, casting to obtain the white alloy for the bearing bush of the internal combustion engine after refining. The process flow is simple, the elements are ensured to be uniformly distributed in the alloy, and the mechanical property of the alloy is improved.)

1. The white alloy for the bearing bush of the internal combustion engine is characterized by comprising the following components in percentage by weight: 3-4% of Cu, 7-9% of Sb, 0.18-0.3% of Ni, 0.8-1.2% of Cd, and the balance of Sn and inevitable impurities.

2. The white alloy for an internal combustion engine bearing shell according to claim 1, which comprises the following components in percentage by weight: 3-4% of Cu, 7-9% of Sb, 0.2% of Ni, 0.8-1.2% of Cd, and the balance of Sn and inevitable impurities.

3. The white alloy for an internal combustion engine bearing shell according to claim 2, which comprises the following components in percentage by weight: 3.5% of Cu, 8% of Sb, 0.2% of Ni, 1% of Cd, and the balance of Sn and unavoidable impurities.

4. A preparation method of white alloy for an internal combustion engine bearing bush is characterized by comprising the following steps:

s1, weighing the copper-nickel intermediate alloy, antimony, cadmium and tin according to the weight percentage of the components of the white alloy for the bearing bush of the internal combustion engine as claimed in any one of claims 1 to 3;

s2, putting all the weighed copper-nickel intermediate alloy, antimony and 2/3 total weight of tin into a smelting furnace, starting the smelting furnace, heating to 660-680 ℃, preserving heat to completely melt the mixed materials in the smelting furnace, adding the rest tin raw materials to melt and fully stir, adding cadmium to melt when the temperature of the alloy liquid is reduced to 380-420 ℃, adding a refining agent to refine and remove slag at 380-420 ℃ after the cadmium is completely melted, and refining for 5-10 min;

and S3, casting at 380-420 ℃ after refining to obtain the white alloy for the bearing bush of the internal combustion engine.

5. The method for preparing the white alloy for the bearing shell of the internal combustion engine as claimed in claim 4, wherein: the melting temperature in the S2 is 660-680 ℃.

6. Use of the white alloy for an internal combustion engine bearing shell according to any one of claims 1 to 3 or the white alloy prepared by the preparation method according to any one of claims 4 to 5 in a bearing with a maximum load specific pressure of 32MPa and a working temperature of less than 100 ℃.

Technical Field

The invention relates to a bearing alloy, in particular to a white alloy for a bearing bush of an internal combustion engine and a preparation method thereof.

Background

The bearing bush of the internal combustion engine such as a marine low-speed diesel engine, a medium-speed diesel engine and the like is used as a heavy part of equipment, and the bearing alloy material is required to have good bearing capacity, running-in property, embedding property and the like so as to meet the working condition requirements. The white alloy has good soft indexes such as antifriction property, embedding property, seizure resistance and the like, but the indexes such as hardness, bearing capacity and the like of the conventional white alloy are lower, particularly the power density of an internal combustion engine is improved, higher requirements are put forward for the bearing capacity and the like of a bearing material, and the development of the white alloy with higher bearing capacity becomes market demands.

Disclosure of Invention

The invention aims to provide a white alloy for an internal combustion engine bearing bush and a preparation method thereof, which have excellent comprehensive mechanical properties and can meet the requirement of high bearing capacity of the bearing bush.

The white alloy for the bearing bush of the internal combustion engine comprises the following components in percentage by weight: 3-4% of Cu, 7-9% of Sb, 0.18-0.3% of Ni, 0.8-1.2% of Cd, and the balance of Sn and inevitable impurities.

Further, the paint comprises the following components in percentage by weight: 3-4% of Cu, 7-9% of Sb, 0.2% of Ni, 0.8-1.2% of Cd, and the balance of Sn and inevitable impurities.

Further, the paint comprises the following components in percentage by weight: 3.5% of Cu, 8% of Sb, 0.2% of Ni, 1% of Cd, and the balance of Sn and unavoidable impurities.

A preparation method of white alloy for an internal combustion engine bearing bush comprises the following steps:

s1, weighing a copper-nickel intermediate alloy, antimony, cadmium and tin according to the weight percentage of the components of the white alloy for the bearing bush of the internal combustion engine;

s2, putting all the weighed copper-nickel intermediate alloy, antimony and 2/3 total weight of tin into a smelting furnace, starting the smelting furnace, heating to 660-680 ℃, preserving heat to completely melt the mixed materials in the smelting furnace, adding the rest tin raw materials to melt and fully stir, adding cadmium to melt when the temperature of the alloy liquid is reduced to 380-420 ℃, adding a refining agent to refine and remove slag at 380-420 ℃ after the cadmium is completely melted, and refining for 5-10 min;

and S3, casting at 380-420 ℃ after refining to obtain the white alloy for the bearing bush of the internal combustion engine.

The melting temperature in the S2 is 660-680 ℃.

The white alloy for the bearing bush of the internal combustion engine or the white alloy prepared by the preparation method is applied to a bearing with the highest load specific pressure of 32MPa and the working temperature of less than 100 ℃.

Compared with the prior art, the invention has the following beneficial effects.

1. The invention limits the weight percentage of Ni element to be 0.18-0.3%, the addition of Ni element can promote the nucleation and crystallization of Cu6Sn5 phase, refine needle-shaped and star-shaped crystal grains of Cu6Sn5, more effectively retard the aggregation of SbSn square phase crystal grains, and improve the alloy strength. If the addition amount of the Ni element is less than 0.18 percent, the refining effect is not obvious, and the mechanical property of the alloy is not greatly improved; if the addition amount of the Ni element is more than 0.3 percent, the mechanical property is not greatly improved, and meanwhile, the excessive Ni element, the Cu element and the Sn element form a complex brittle state to reduce the plasticity and the fatigue strength of the alloy.

2. The invention limits the weight percentage of Cd element to be 0.8-1.2%, Cd element can form solid solution with Sn, the solid solution plays a role in solid solution hardening, and the strength is increased under the condition of not influencing the alloy rigidity; the Cd can inhibit the growth of hard phase SnSb in the alloy and play a role in fine grain strengthening. If the addition of Cd is less than 0.1%, the strength is improved to a limited extent, and the influence on the mechanical property of the alloy is small; if the addition amount of Cd is higher than 2%, a brittle phase is generated in the alloy, and the plasticity of the alloy is reduced. The weight percentage of Cd element is limited to 0.8-1.2% by combining the rigidity of the alloy.

3. The preparation method provided by the invention has the advantages that the process flow is simple, the elements are uniformly distributed in the alloy, and the mechanical property of the alloy is improved.

Detailed Description

The present invention will be described in detail below.

The embodiment I provides a white alloy for an internal combustion engine bearing bush, which comprises the following components in percentage by weight: 3.5% of Cu, 8% of Sb, 0.22% of Ni, 1% of Cd, and the balance of Sn and inevitable impurities. The preparation method of the white alloy for the bearing bush of the internal combustion engine comprises the following steps.

S1, weighing a copper-nickel intermediate alloy, antimony, cadmium and tin according to the weight percentage of the components of the white alloy for the bearing bush of the internal combustion engine;

s2, putting all the weighed copper-nickel intermediate alloy, antimony and 2/3 total weight of tin into a smelting furnace, starting the smelting furnace, heating to 670 ℃ and preserving heat to completely melt the mixed materials in the smelting furnace, then adding the rest tin raw materials to melt and fully stir, adding cadmium to melt when the temperature of alloy liquid is reduced to 410 ℃, adding a refining agent to refine and remove slag after the cadmium is completely melted at 400 ℃, and refining for 8 min;

and S3, casting at the temperature of 400 ℃ after refining to obtain the white alloy for the bearing bush of the internal combustion engine.

The mechanical property of the prepared alloy cast ingot is detected, and the alloy cast ingot is compared with the performance of the existing white alloy for the bearing bush, and the result is shown in table 1.

TABLE 1 mechanical Properties of the alloys

	hardness/HBS	Tensile strength/MPa	Yield strength/MPa	Elongation/percent	Fatigue strength/Mpa
						Example one	29.4	90.0	71.0	9.0	35
ZSnSb8Cu4	24.5	77.0	59.8	17.8	27
						ZSnSb11Cu6	27.6	76.8	64.8	2.9	30

ZSnSb8Cu4 and ZSnSb11Cu6 are currently common as-cast tin-based bearing alloys, wherein the ZSnSb8Cu4 has the following elemental composition: 8% of Sb, 4% of Cu, and the balance of Sn and inevitable impurities; the elemental composition of znssb 11Cu6 was 11% Sb, 6% Cu, and the balance Sn and inevitable impurities.

As can be seen from Table 1, the white alloy for the bearing shell of the internal combustion engine prepared in the first example has higher hardness, tensile strength, yield strength and fatigue strength than the conventional ZSnSb8Cu4 and ZSnSb11Cu 6. The elongation can reach 9.0, the fatigue strength reaches 35Mpa, the comprehensive mechanical property is excellent, the strength performance is met, the plasticity is better, the bearing is suitable for the bearing with the highest load specific pressure of 32MPa and the working temperature of less than 100 ℃, and the service reliability and the service life of the bearing are improved.

The second embodiment provides a white alloy for an internal combustion engine bearing bush, which comprises the following components in percentage by weight: 3% of Cu, 9% of Sb, 0.18% of Ni, 1.2% of Cd, and the balance of Sn and inevitable impurities. The preparation method is the same as the first embodiment. Through mechanical property tests, the hardness, tensile strength, yield strength and fatigue strength of the alloy are all higher than those of the existing ZSnSb8Cu4 and ZSnSb11Cu 6.

In a third embodiment, a white alloy for an internal combustion engine bearing shell comprises the following components in percentage by weight: 4% of Cu, 7.5% of Sb, 0.25% of Ni, 1% of Cd, and the balance of Sn and unavoidable impurities. The preparation method is the same as the first embodiment. Through mechanical property tests, the hardness, tensile strength, yield strength and fatigue strength of the alloy are all higher than those of the existing ZSnSb8Cu4 and ZSnSb11Cu 6.

The fourth embodiment provides a white alloy for an internal combustion engine bearing bush, which comprises the following components in percentage by weight: 3.2% of Cu, 7% of Sb, 0.28% of Ni, 0.9% of Cd, and the balance of Sn and inevitable impurities. The preparation method is the same as the first embodiment. Through mechanical property tests, the hardness, tensile strength, yield strength and fatigue strength of the alloy are all higher than those of the existing ZSnSb8Cu4 and ZSnSb11Cu 6.

The embodiment five discloses a white alloy for an internal combustion engine bearing bush, which comprises the following components in percentage by weight: 3.8% of Cu, 8% of Sb, 0.2% of Ni, 1% of Cd, and the balance of Sn and unavoidable impurities. The preparation method is the same as the first embodiment. Through mechanical property tests, the hardness, tensile strength, yield strength and fatigue strength of the alloy are all higher than those of the existing ZSnSb8Cu4 and ZSnSb11Cu 6.

The sixth embodiment provides a white alloy for an internal combustion engine bearing bush, which comprises the following components in percentage by weight: 3.5% of Cu, 7% of Sb, 0.2% of Ni, 0.95% of Cd, and the balance of Sn and inevitable impurities. The preparation method is the same as the first embodiment. Through mechanical property tests, the hardness, tensile strength, yield strength and fatigue strength of the alloy are all higher than those of the existing ZSnSb8Cu4 and ZSnSb11Cu 6.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.