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

Method for preparing pore-space feature controlled lightweight high-strength porous nickel titanium memory alloys

A technology of memory alloy and porous nickel, which is applied in the field of preparation of porous nickel-titanium shape memory alloy, can solve the problems of strength and superelasticity decline, poor controllability of porosity, large randomness of sample performance, etc., and achieve high-strength mechanical properties High performance, high porosity and good controllability

Inactive Publication Date: 2009-07-15
SOUTH CHINA UNIV OF TECH
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

These methods have three disadvantages: first, the controllability of the porosity of the prepared samples is not high, and the properties of the samples are relatively random; second, it is difficult to obtain porous nickel-titanium alloys with large-scale pore structures, uniform pore distribution, and high porosity ; The third is that when the porosity increases, the strength and superelasticity of the sample decrease
In short, although adding ammonium bicarbonate as a pore-forming agent can improve the pore characteristics to a certain extent, it is not easy to accurately control the loss of the pore-forming agent during the preparation process, the performance of the prepared sample is not stable enough, and the process repeatability needs to be improved.

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 preparing pore-space feature controlled lightweight high-strength porous nickel titanium memory alloys
  • Method for preparing pore-space feature controlled lightweight high-strength porous nickel titanium memory alloys
  • Method for preparing pore-space feature controlled lightweight high-strength porous nickel titanium memory alloys

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] Use pure titanium powder (average particle size 48 μm) and pure nickel powder (average particle size 57 μm) according to nickel:titanium atomic ratio 50.8:49.2 and mix thoroughly for 24 hours to obtain raw material powder A. Add 20wt% urea (average particle size 700 μm, maximum and minimum particle size 600 and 900 μm) to powder A, mix for 12 hours to make powder B. Powder B was pressed at 50 MPa into a cylindrical green body with a diameter of 16 mm, a length of 15 mm and a porosity of 45.76%. Put the billet into an electric heating tubular sintering furnace, heat it to 250°C under the protection of argon with a purity higher than 99.99% and keep it warm for 1 hour, in order to remove the pore-forming agent urea and activate the billet. Then it was heated to 840°C at a heating rate of 15°C / min and kept for 5 minutes. Finally, it was heated to 1000°C at a heating rate of 10°C / min and kept for 3 hours. Finally, a porous nickel-titanium shape memory alloy with high poro...

Embodiment 2

[0035] Use pure titanium powder (average particle size 48 μm) and pure nickel powder (average particle size 57 μm) according to nickel:titanium atomic ratio 51:49 and mix thoroughly for 24 hours to obtain raw material powder A. Add 30wt% urea (average particle size 350 μm, maximum and minimum particle size is 300 and 450 μm respectively) in powder A, make powder B after mixing 12 hours, under 200MPa, powder B is pressed into diameter 16 millimeters, length 18 mm, a cylindrical green body with a porosity of 61.59%. The billet is put into a tube-type sintering furnace, heated to 300°C under the protection of argon with a purity higher than 99.99%, and kept for 1 hour. Then it was heated to 820°C at a heating rate of 30°C / min and kept for 10 minutes. Finally, it was heated to 950° C. at a heating rate of 20° C. / min and kept for 3 hours. Finally, a porous nickel-titanium shape memory alloy with uniform distribution of pores was synthesized.

[0036] figure 2 It is a micrograp...

Embodiment 3

[0038] Use pure titanium powder (average particle size 48 μm) and pure nickel powder (average particle size 57 μm) according to the atomic ratio of nickel and titanium 50:50 and mix thoroughly for 24 hours to obtain raw material powder A. Add 10wt% urea (average particle size 500 μm, maximum and minimum particle size 450 and 600 μm) to powder A, mix for 12 hours to make powder B. Powder B was pressed into a cylindrical green body with a diameter of 16 mm, a length of 20 mm and a porosity of 35.02% at 100 MPa. The billet is put into an electric heating tubular sintering furnace, heated to 200°C under the protection of argon with a purity higher than 99.99%, and kept for 2 hours. Then, after heating to 860° C. at a heating rate of 10° C. / min, keep the temperature for 5 minutes. Then heat it up to 1150°C at a heating rate of 15°C / min and keep it warm for 1 hour.

[0039] Figure 3-1 is the DSC curve of the prepared sample, P m Represents martensitic transformation, P r Repre...

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
particle sizeaaaaaaaaaa
particle sizeaaaaaaaaaa
densityaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for preparing a lightweight high-strength porous nickel-titanium memory alloy with controllable pore characteristics. The method comprises: (1) uniformly mixing pure titanium powder and pure nickel powder; (2) using 10-30% of the mass For this purpose, fully mix a new type of pore-forming agent-urea granules with the mixed powder obtained in step (1); (3) press the powder obtained in step (2) into a powder with an original porosity of 30% to 60% and evenly distributed pores Sample blank; (4) heating the blank to decompose and remove the pore-forming agent urea; (5) heat up and keep warm according to the cascade heating method, and carry out cascade sintering to obtain uniform distribution of pores, low density, high strength and good superelasticity porous nickel-titanium shape memory alloy. The invention has good process adaptability, simple preparation process and simple and convenient pore-forming agent removal process; the prepared product has good pore property adjustability, high porosity, high compressive strength, stable mechanical properties and excellent linear superelastic deformation ability.

Description

technical field [0001] The invention relates to the preparation of a porous nickel-titanium shape memory alloy, in particular to a method for preparing a porous nickel-titanium shape memory alloy with good controllability of pore characteristics, low density, high strength and stable mechanical properties. Background technique [0002] Nickel-titanium shape memory alloy is a new type of functional material with unique shape memory effect, phase transition superelasticity, good biocompatibility, corrosion resistance, wear resistance and high fatigue resistance. The above-mentioned excellent characteristics of nickel-titanium alloy make it have unique advantages as a biomedical material. At present, dense nickel-titanium shape memory alloys have been widely used in medical fields such as oral cavity, orthopedics, neurosurgery, cardiovascular system, and urinary system. With the development of interventional medicine, nickel-titanium shape memory alloys involve a wider range o...

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): C22C1/04B22F3/16C22C19/03
Inventor 张新平李大圣张宇鹏
Owner SOUTH CHINA UNIV OF TECH
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