Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of surface-carburizing gradient hard alloy

A hard alloy, surface carburizing technology, applied in metal processing equipment, metal material coating technology, coating, etc., can solve the problems of long carburizing time, low efficiency, grain growth, etc., and achieve improved carburizing Efficiency, simple process, and small particle size

Active Publication Date: 2017-07-28
SICHUAN UNIV
View PDF4 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The present invention aims at the problems of severe grain growth, long carburizing time and low efficiency in the "sintering + carburizing" process when preparing gradient cemented carbide with surface carburization, and proposes to remove the cemented carbide compact first. Forming agent to form a porous green body, and then SiO 2 coated TiH 2 core / shell powder, graphene, BaCO 3 The mixed planetary ball mill is uniformly mixed to form a hydrogen-containing carburizing medium, and then the porous green body is placed in the carburizing medium and compacted, and finally the surface carburized gradient cemented carbide is formed in situ during liquid phase sintering

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
  • Preparation method of surface-carburizing gradient hard alloy

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0018] Example 1: Prepare the surface carburized gradient cemented carbide according to the following steps:

[0019] (1) Preparation of the release agent cemented carbide green body: Weigh various raw material powder ingredients according to weight percentage, among which Co accounts for 8wt%, TiC accounts for 5wt%, TaC accounts for 1wt%, and WC is the balance; the weighed powder Mixed and ball milled for 48 hours, filtered with a 400-mesh screen, dried at 90°C, mixed with butadiene rubber molding agent according to 60% of the weight of the cemented carbide powder, and pressed under a pressure of 320MPa to obtain a cemented carbide green body; cemented carbide raw The blank is kept in a vacuum sintering furnace at 620°C for 2 hours, the heating rate is 2°C / min, and the vacuum degree is 12Pa, forming a cemented carbide green body with a porosity of 28% and the removal of the forming agent;

[0020] (2) Preparation of hydrogen-containing carburizing medium: first weigh TiH with...

example 2

[0023] Example 2: Prepare the gradient cemented carbide of surface carburizing according to the following steps:

[0024] (1) Preparation of the release agent cemented carbide green body: Weigh various raw material powder ingredients according to weight percentage, among which Co accounts for 15wt%, and WC is the balance; mix the weighed powder and pass through 72h ball milling, 400 mesh screen Filtrate, dry at 100°C, mix 100% of the weight of the cemented carbide powder into a butadiene rubber molding agent, press and form under a pressure of 380MPa to obtain a cemented carbide green body; keep the cemented carbide green body at 750°C for 3 hours in a vacuum sintering furnace , the heating rate is 4°C / min, the vacuum degree is 15Pa, and the cemented carbide green body with a porosity of 28% and the removal of the molding agent is formed;

[0025] (2) Preparation of hydrogen-containing carburizing medium: first weigh TiH with a particle size of 0.8 μm 2 The powder is added to...

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
Flexural strengthaaaaaaaaaa
Login to View More

Abstract

The invention discloses a preparation method of a surface-carburizing gradient hard alloy. The preparation method is characterized in that heat preservation is conducted for 2-4 h at the temperature ranging from 550 DEG C to 750 DEG C, and a hard alloy green body of a removal forming agent with the porosity ranging from 25% to 40% is formed; then, core / shell structure powder, graphene and BaCO3 are mixed according to the weight percentage being 1 to 2 to 1 to prepare a hydrogen-containing carburizing medium, wherein TiH2 is wrapped by SiO2 in the core / shell structure powder, the thickness of the graphene is smaller than 3 nm, the layer number of the graphene is smaller than 3, and the specific surface area of the graphene is larger than 250 m<2> / g; then, the green body is buried in the hydrogen-containing carburizing medium and is compacted under the pressure ranging from 5 MPa to 15 MPa; and finally, liquid-phase sintering is conducted, and the surface-carburizing gradient hard alloy is prepared. The preparation method solves the problems that an existing process is serious in grain growth, long in carburizing time and low in efficiency, and the surface-carburizing gradient hard alloy is prepared in the sintering process.

Description

technical field [0001] The invention relates to a method for preparing hard alloy, in particular to a method for preparing surface carburized gradient hard alloy, which belongs to the field of hard materials. Background technique [0002] As a new tool material, cemented carbide is based on refractory metal hard compounds (usually referring to carbides, nitrides, borides and silicides of transition elements in the periodic table of elements, etc.), based on iron group Metals (such as cobalt, nickel, iron) are used as bonding metals, which are high hardness and high wear resistance materials manufactured by powder metallurgy. However, it is difficult for homogeneous materials to meet more and more complex working conditions. With the concept of gradient cemented carbide, people pay attention to improving material properties by carburizing the surface. [0003] CN102002664A discloses a preparation method of gradient structure cemented carbide. First, the surface oxidation met...

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): C22C29/08C22C1/05C23C8/64B22F3/10
CPCC22C1/051C22C29/08C23C8/64B22F3/1007B22F3/1035B22F2999/00B22F2998/10B22F2201/30B22F2207/01B22F3/1021B22F2201/20B22F1/10B22F3/02
Inventor 郭智兴熊计陈诚
Owner SICHUAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com