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

Manufacturing method of iron-based powder metallurgy part

An iron-based powder metallurgy and manufacturing method technology, applied in the field of powder metallurgy, can solve the problems of difficulty in increasing density or/and surface density, failing to improve mechanical properties and strength, low production efficiency, etc. / and the effect of local density, low cost, and improved mechanical properties

Active Publication Date: 2019-04-30
NBTM NEW MATERIALS GRP
View PDF7 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

It proposes to use annealing to improve the structure and reduce the hardness, but for products with high carbon content, the reduction in hardness by annealing is limited, and the annealing time is too long, resulting in low production efficiency
[0008] Therefore, for high-carbon iron-based powder metallurgy parts, it is difficult to increase the density or / and surface density through extrusion, shaping, re-pressing, surface rolling, and transverse rolling, and the mechanical properties and strength cannot be improved. the goal of

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
  • Manufacturing method of iron-based powder metallurgy part
  • Manufacturing method of iron-based powder metallurgy part
  • Manufacturing method of iron-based powder metallurgy part

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] Prepare the raw materials, the proportion of which is (mass percentage): Molybdenum 0.85% Fe-Mo alloy powder is 98.85%; carbon is 0.65%, and the content is 0.5% lubricant; the above-mentioned mixed powder is compressed under a pressure of 600MPa Density 7.10g / cm 3 Green gears;

[0038] Sintering: sintering in nitrogen containing 3vol% hydrogen, the sintering temperature is 1120℃, and the sintering time is 30 minutes;

[0039] Induction heating: Place the sintered gear in an induction coil for induction heating. The power frequency is 120kHZ, the heating time is 1.8S, the surface temperature is measured by infrared radiation at 950℃, and the heating depth of the tooth root is 2.0mm;

[0040] Densification: transfer the workpiece to the surface rolling equipment, perform surface rolling densification, cool to room temperature after densification, and measure the depth of the densification layer, which is 0.4mm;

[0041] Quenching and tempering: quenching and tempering the parts t...

Embodiment 2

[0047] Prepare the raw materials, the proportion of which is (mass percentage): 0.85% molybdenum iron-molybdenum alloy powder is 98.85%; carbon is 0.65%, and the content is 0.5% lubricant; the above-mentioned mixed powder is compressed under a pressure of 600MPa Density 7.10g / cm 3 The green gear blank, the outer diameter of the blank is 80mm, and the inner diameter is 40mm;

[0048] Sintering: sintering in nitrogen containing 3vol% hydrogen, sintering temperature 1250℃, sintering time 30 minutes;

[0049] Induction heating: The sintered gear is placed in an induction coil for induction heating. The power supply frequency is 25kHZ, the heating time is 15S, and the part temperature is measured at 980℃ by infrared radiation;

[0050] Densification: transfer the workpiece to a recompression press, perform recompression densification, and cool to room temperature after densification;

[0051] Quenching and tempering: the parts are quenched and tempered to achieve the required mechanical pr...

Embodiment 3

[0054] Prepare the raw materials, the proportion of which is: iron alloy powder (3.0% for chromium, 0.5% for molybdenum, less than 1% of unavoidable substances, and iron as the balance) 50%, pure iron powder 48.7%; carbon 0.8 %, and then add a lubricant with a content of 0.5%; the above-mentioned mixed powder is compressed to a density of 7.2g / cm under a pressure of 700MPa 3 Cam green body;

[0055] Sintering: sintering in nitrogen containing 3vol% hydrogen, sintering temperature 1250℃, sintering time 30 minutes;

[0056] Induction heating: Place the sintered cam in the induction coil for induction heating. The power frequency is 20kHZ, the heating time is 17S, and the surface temperature is 980℃ measured by infrared radiation;

[0057] Densification: transfer the workpiece to the extrusion densification equipment, perform extrusion densification, cool to room temperature after densification, and measure the depth of the densification layer, which is 0.8mm;

[0058] Quenching and temp...

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
Outer diameteraaaaaaaaaa
The inside diameter ofaaaaaaaaaa
Login to View More

Abstract

The invention relates to a manufacturing method of an iron-based powder metallurgy part. The manufacturing method comprises the following steps of designing materials, mixing materials, forming, sintering, induction heating, densification, quenching and tempering. According to the manufacturing method of the iron-based powder metallurgy part, hot-state densification is performed immediately afterinduction heating is adopted, the compactness is small, the efficiency is high, the thickness of the compact layer is large, compared with a traditional powder metallurgy process, the preparation method disclosed by the invention is relatively low in cost and relatively high in efficiency, the density of the prepared product is higher, the overall density can exceed 7.60g / cm3, close to the level of the powder forging, the relative density of the surface can reach 99% or above, the surface densification is basically realized, the overall density or / and the local density of the high-carbon powder metallurgy product is greatly improved, and the mechanical property of the part is effectively improved.

Description

Technical field [0001] The invention belongs to the technical field of powder metallurgy, and in particular relates to a method for manufacturing iron-based powder metallurgy parts. Background technique [0002] Powder metallurgy is an effective process for producing gears with high strength and complex shapes. At present, through the use of high-performance powder, molding, sintering and special post-processing, the powder metallurgy process has been able to produce a density exceeding 7.4g / cm 3 Parts. Re-pressing and re-burning technology can greatly increase the density of products. After forming and sintering with ordinary atomized iron powder, the density of iron-based powder metallurgy parts can only reach 7.1g / cm 3 about. In order to further increase the density of powder metallurgy parts, a re-pressing and re-sintering process of forming-pre-sintering-re-pressing-secondary sintering can be used. Pre-sintering has two functions. One is to anneal the work-hardened powde...

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
IPC IPC(8): C22C38/42C22C38/44C22C38/58C22C38/04B22F3/02B22F3/10B22F3/24C21D1/18
CPCB22F3/02B22F3/10B22F3/24B22F2003/248C21D1/18C22C38/04C22C38/42C22C38/44C22C38/58
Inventor 包崇玺朱承旭冯伟立
Owner NBTM NEW MATERIALS GRP