Unlock instant, AI-driven research and patent intelligence for your innovation.

High-hardness powder metallurgy low-alloy steel

A technology of low-alloy steel and powder metallurgy, which is applied in the field of sintered components, can solve the problems of high oxygen content and poor compaction performance of chromium-containing low-alloy steel powder, and achieve the effect of low alloy content, light weight and improved compaction performance

Inactive Publication Date: 2012-12-12
CENT SOUTH UNIV
View PDF7 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problems of poor compaction performance and high oxygen content in the existing production of chromium-containing low-alloy steel powder, and can provide a kind of powder rice for the production of low-cost, high-strength, high-hardness parts for automobiles, machinery and other industries Metallurgical Low Alloy Steel

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • High-hardness powder metallurgy low-alloy steel
  • High-hardness powder metallurgy low-alloy steel
  • High-hardness powder metallurgy low-alloy steel

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0013] Composition of the powder metallurgy composition: 30% pure iron powder and 70% iron-based matrix powder. 30% of the pure iron powder is reduced iron powder (less than 74 μm), the purpose is to improve the compaction performance of the mixed powder. The other 70% of the iron-based matrix powder includes the following powders: 2.5% electrolytic copper powder (-200 mesh), 0.8% graphite powder, 0.6% paraffin wax powder, and the balance is low alloy steel powder, including 0.4% chromium, 1.0% nickel , 0.5% molybdenum, the sum of nickel and molybdenum content is 1.5%, and the rest is iron. The low alloy steel powder is prepared by argon atomization method, and the oxygen content of the powder is 0.060%. Its physical properties are shown in the table below.

[0014]

[0015] The mixed powder is mixed (dry mixed in a drum mixer for 1h), pressed (molded, 600MPa), sintered (1180°C, H 2 atmosphere protection), tempering in air at 180°C for 1h.

[0016] The properties of the...

Embodiment 2

[0018] Composition of the powder metallurgy composition: 20% pure iron powder and 80% iron-based matrix powder. 20% of the pure iron powder is reduced iron powder (-200 mesh), the purpose is to improve the compaction performance of the mixed powder. The other 80% iron-based matrix powders include the following powders: 2.0% electrolytic copper powder (-200 mesh), 0.4% graphite powder, 0.2% paraffin wax powder, and the balance is low alloy steel powder, including 0.5% chromium, 1.5% nickel , 0.4% molybdenum, the sum of nickel and molybdenum content is 1.9%, and the rest is iron. The low alloy steel powder is prepared by argon atomization method, and the oxygen content of the powder is 0.058%. Its physical properties are shown in the table below.

[0019]

[0020] The mixed powder is mixed (dry mixed in a drum mixer for 1h), pressed (molded, 600MPa), sintered (1180°C, H 2 atmosphere protection), tempering in air at 180°C for 1h.

[0021] Properties of powder metallurgy lo...

Embodiment 3

[0023] The composition of the powder metallurgy composition: 10% pure iron powder and 90% iron-based matrix powder, wherein 10% of the pure iron powder is reduced iron powder (-200 mesh), the purpose is to improve the compaction performance of the mixed powder. The other 90% iron-based matrix powders include the following powders: 1.5% electrolytic copper powder (-200 mesh), 0.6% graphite powder, 0.5% paraffin wax powder, and the balance is low alloy steel powder, which includes 0.6% chromium, 1.1% nickel, 0.5% molybdenum, the sum of nickel and molybdenum is 1.5%, and the rest is iron. The low alloy steel powder is prepared by argon atomization, and the oxygen content of the powder is 0.062%. Its physical properties are shown in the table below.

[0024]

[0025] The mixed powder is mixed (dry mixed in a drum mixer for 1h), pressed (molded, 600MPa), sintered (1180°C, H 2 atmosphere protection), tempering in air at 180°C for 1h.

[0026] Properties of powder metallurgy lo...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
densityaaaaaaaaaa
densityaaaaaaaaaa
densityaaaaaaaaaa
Login to View More

Abstract

The invention discloses low-cost and high-hardness powder metallurgy low-alloy steel comprising 70-90 percent of iron-based powder and 30-10 percent of reduced iron powder. The low-cost and high-hardness powder metallurgy low-alloy steel is characterized in that the 70-90 percent of iron-based powder comprises 1.0-2.5 percent of electrolytic copper powder, 0.4-1.0 percent of graphite powder, 0.2-0.8 percent of paraffin lubricating agent and the balance of low-alloy steel powder; and the low-alloy steel powder comprises 0.4-0.6 percent of chromium, 1.0-1.5 percent of nickel, 0.4-0.5 percent ofmolybdenum and the balance of Fe, wherein the content summation of the nickel and the molybdenum is not more than 2.0 percent. The mixture is mixed, pressed and sintered and then tempered in the air at the temperature of 180 DEG C for 1h. Proved by the embodiment, the density of the powder metallurgy alloy is 6.81-6.95g / cm<3>, the hardness can reach 43HRC (Rockwell Hardness), the tensile strengthcan reach 731N / mm<2> and the hardness and the strength of the alloy can be adjusted according to the addition of the reduced iron powder, the alloy components and the sintering density.

Description

technical field [0001] The invention relates to a low-cost, high-hardness powder metallurgy low-alloy steel, especially suitable for preparing various high-hardness, high-strength sintered components. Background technique [0002] With the development of automobile, machinery, electronic appliances and other industries, powder metallurgy materials have been more and more widely used, especially iron-based powder metallurgy materials, which have always occupied a dominant position and are widely used in automobile braking, transmission, etc. . Since most iron-based powder metallurgy materials are used in the automotive industry, production cost and product performance have become the main driving forces for the development of the powder metallurgy industry. In recent years, many new processes and alloy systems have emerged, all of which are aimed at improving the cost performance of powder metallurgy iron-based parts. [0003] Pre-alloyed powders are more and more used in t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): B22F1/00C22C38/44
Inventor 罗丰华王翔高翔
Owner CENT SOUTH UNIV