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

Method for promoting densification of metal blank by utilizing hydrogen absorption expansion effect of metal

A metal body and densification technology, which is applied in the direction of improving process efficiency, additive manufacturing, and improving energy efficiency, can solve problems such as production efficiency and product size limitation, product anisotropy, product size limitation, etc., to achieve Simple production equipment and molds, uniform structure, and the effect of inhibiting grain growth

Active Publication Date: 2019-11-01
CENT SOUTH UNIV
View PDF6 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Hot pressing and sintering can easily lead to anisotropy of the product, and the production efficiency and product size are limited
Spark plasma sintering increases the pulse current on the basis of hot pressing sintering, promotes sintering densification, and can complete the sintering of fully dense materials in a short period of time. The disadvantage is that the size of the product is limited and it is difficult to scale up.
Therefore, the above technologies all have disadvantages such as high cost, low efficiency, and limited product size.

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
  • Method for promoting densification of metal blank by utilizing hydrogen absorption expansion effect of metal

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046]1. Put a titanium product with a density of 98% (industrial pure titanium, titanium content > 98%) into a stainless steel mold, and fill the space between the product and the mold with titanium powder with an average particle size of 45 microns (the filling volume of titanium powder accounts for 40% of the inner cavity volume), the mold is packaged and fastened. (due to the gaps left between the mold modules; these gaps are good ventilation holes)

[0047] 2. Put the assembled mold into a hydrogen furnace, heat it to 600 degrees Celsius in a vacuum, feed hydrogen (hydrogen pressure 1 bar), keep feeding hydrogen and keep it warm for 10 hours.

[0048] 3. Stop the hydrogen gas flow in the hydrogen furnace, and vacuumize (vacuum degree is less than 10 -3 Pa), the temperature was increased to 750 degrees Celsius, and the furnace was shut down to cool after keeping for 10 hours.

[0049] 4. Turn on the hydrogen furnace, take out and open the mold, and take out the titanium ...

Embodiment 2

[0053] 1. Put a titanium alloy product with a density of 95% (titanium content > 20%) into a stainless steel mold, the fit between the product and the mold is less than 0.1mm, and then seal and fasten the mold. (due to the gaps left between the mold modules; these gaps are good ventilation holes)

[0054] 2. Put the assembled mold into a hydrogen furnace, heat it to 600 degrees Celsius in a vacuum, feed hydrogen (hydrogen pressure 10 bar), keep feeding hydrogen and keep it warm for 10 hours.

[0055] 3. Stop the hydrogen gas flow in the hydrogen furnace, and vacuumize (vacuum degree is less than 10 -3 Pa), the temperature was increased to 750 degrees Celsius, and the furnace was shut down to cool after keeping for 10 hours.

[0056] 4. Turn on the hydrogen furnace, take out and open the mold, and take out the titanium alloy product with a density greater than 99.5%.

Embodiment 3

[0060] 1. Put the copper alloy (copper content > 60%) product with a density of 95% into a stainless steel mold, and fill the space between the product and the mold with titanium powder with an average particle size of 45 microns (the filling volume of titanium powder accounts for 30% of the inner cavity volume of the mold. %), package and fasten the mold (because there are gaps between the mold modules; these gaps are good ventilation holes).

[0061] 2. Put the assembled mold into a hydrogen furnace, heat it to 600 degrees Celsius in a vacuum, feed hydrogen (hydrogen pressure 1 bar), keep feeding hydrogen and keep it warm for 10 hours.

[0062] 3. Stop the hydrogen flow in the hydrogen furnace, vacuumize (vacuum degree is less than 10-3Pa), raise the temperature to 750 degrees Celsius, keep the furnace for 10 hours, and then stop the furnace to cool.

[0063] 4. Turn on the hydrogen furnace, take out and open the mold, and take out the copper alloy product with a density gre...

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

No PUM Login to View More

Abstract

The invention relates to a method for promoting densification of a metal blank by utilizing the hydrogen absorption expansion effect of metal. The hydrogen absorption expansion effect means that certain metal blocks or metal powders absorb hydrogen under the condition of a hydrogen atmosphere and a certain temperature to generate a volume expansion effect; under the constraint of a rigid die sleeve, the periphery of the metal blank needing densification treatment is filled with hydrogen absorption metal; and the volume expansion effect is generated through the hydrogen absorption of the metal,so that internal pores of the metal blank are closed due to the internal pressure, and the density of the metal blank is improved. The method for preparing high-density or full-density metal materialunder the medium-low temperature and the hydrogen atmosphere is provided, and the method can be used as a novel powder metallurgy densification technology and a method for eliminating the residual pores in the metal material so as to improve various properties of the material.

Description

technical field [0001] The invention relates to a method for densification of metals, alloys and metal-based composite materials; in particular, it relates to a method for increasing the densification of metal blanks by using the expansion effect of metal hydrogenation. Background technique [0002] During the processing of metal materials, certain pores are often generated inside the material. Shrinkage cavities and pores often exist in cast alloys. For powder metallurgy materials, there are residual pores in the sintered body of many material systems. According to reports, metal materials manufactured by additives will have tiny pores due to the influence of raw materials and processes. In the process of metal welding, micropores or air bubbles generated at the weld are serious defects. In addition, interfacial reactions may lead to porosity during the fabrication of metal composites. Pores in metal materials are one of the main defects that affect the performance of p...

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): B22F3/15
CPCB22F3/156Y02P10/25B33Y40/20B22F2999/00B22F2998/10B22F10/60B22F10/62B22F10/64B22F2201/013B22F2203/05B22F3/005B22F10/66B33Y10/00B22F10/00B22F2003/153
Inventor 周承商刘咏孙沛刘彬
Owner CENT SOUTH UNIV