Method for improving high-temperature creep resistance of rare-earth-containing magnesium alloy by virtue of anomalous twin crystals

A technology of creep resistance and rare earth magnesium, which is applied in the field of high temperature creep resistance, can solve the problems of increased production cost, increased alloy density, and aggravated rare earth elements, etc., and achieves low environmental protection cost, improved creep resistance, and applicable materials wide range of effects

Inactive Publication Date: 2017-07-25
CENT SOUTH UNIV
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At the same time, the addition of heavy rare earth elements not only increases the alloy density, but also increases the production cost

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 improving high-temperature creep resistance of rare-earth-containing magnesium alloy by virtue of anomalous twin crystals
  • Method for improving high-temperature creep resistance of rare-earth-containing magnesium alloy by virtue of anomalous twin crystals
  • Method for improving high-temperature creep resistance of rare-earth-containing magnesium alloy by virtue of anomalous twin crystals

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] The raw material used in this embodiment is as-cast Mg-6Gd-3Y-1Zn-0.4Zr magnesium alloy. The average grain size of the as-cast state is about 70 μm. The orientation of the grains is analyzed based on the electron backscattering technique, and the loading direction is selected according to the result of the orientation distribution. At 300℃, pre-compress the test piece along the direction of the angle 20~70° with the normal direction of the base surface, and the compression rate is 0.003s -1 , The amount of strain is about 0.005 to 0.05.

[0026] The distribution map of the tissue orientation of the specimen after compression is as follows figure 1 As shown in (a), the (0001) basal pole distribution map of the twin crystal grain matrix A, B, C and their corresponding twins A’, B’, C’ figure 1 (b) made. will figure 1 (b) The area is divided, where LD (Loading Direction) is the loading direction, TD (Transverse Direction) is 90° transverse to the loading direction. When comp...

Embodiment 2

[0029] In this embodiment, the raw material used is Mg-6Gd-3Y-0.4Zr hot-rolled sheet. After homogenization annealing at 500℃ for 2h, the average grain size is about 100μm. At 30℃, 0.03s -1 The test piece is pre-stretched in the direction of the angle between the lower edge and the normal direction of the base surface at 20-70°, and the strain is about 0.01-0.03.

[0030] Analyze the grain orientation of the tensile specimen based on the electron backscattering technique, and obtain the orientation distribution image 3 (a), draw the (0001) basal plane pole figure containing the twin crystal grain matrix and divide its area. When stretched along the loading direction, 3 is the normal twin zone and 4 is the abnormal twin zone, such as image 3 (b) Shown. From image 3 (b) It can be seen that the angle between the loading direction and the normal direction of the (0001) basal plane of these grains is mainly concentrated at 20-70°, which meets the 15-75° abnormal twinning criterion. ...

Embodiment 3

[0033] In this embodiment, the raw material used is Mg-2Y magnesium alloy hot-rolled sheet, and after homogenization annealing at 450° C. for 2 hours, the average grain size is about 120 μm. It is pre-cured repeatedly at 150°C. Due to the particularity of the repeated bending deformation method, the tissues on both sides of the neutral layer will be subjected to loads in two opposite directions during the repeated bending process. The appropriate bending method should be selected to ensure that the base surface of the grain is 15-60° with the loading direction, and the cumulative strain is about 0.002 to 0.04.

[0034] Orientation distribution of tissue after pre-deformation treatment Figure 5 (a) Analyze the (0001) basal pole figure containing twin crystal grains Figure 5 (b) make and divide areas, Figure 5 In (b) 5 is the normal twin zone corresponding to stretching or compression along the loading direction during repeated bending, and 6 is the abnormal twin zone. by Figu...

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
Login to view more

Abstract

The invention discloses a method for improving the high-temperature creep resistance of rare-earth-containing magnesium alloy by virtue of anomalous twin crystals. According to the method, the rare-earth containing magnesium alloy is subjected to predeformation treatment in the direction forming a 15-75-degree angle with the normal direction of a base plane at 25-300 DEG C, the true strain amount is 0.001-0.1, {10-12} anomalous twin crystals are prearranged in the rare-earth-containing magnesium alloy through deformation, the rare-earth-containing magnesium alloy with the prearranged anomalous twin crystals and rare-earth-containing magnesium alloy without prearranged anomalous twin crystals are subjected to stretching or compression creep property testing correspondingly within the temperature range from 200 to 350 DEG C, compared with the rare-earth-containing magnesium alloy without anomalous twin crystals, the rare-earth-containing magnesium alloy with the anomalous twin crystals has the advantages that the creep stain is obviously reduced, the steady-state creep rate is obviously lowered, and the creep resistance of is remarkably improved under the equal service conditions. The process which is reasonable in design, low in equipment requirement, convenient to operate, low in cost, high in efficiency and capable of stably improving the high-temperature creep resistance of the rare-earth-containing magnesium alloy is provided.

Description

Technical field [0001] The invention relates to a method for improving the high-temperature creep resistance of rare earth magnesium alloys by using abnormal twins, in particular to a method for improving the high-temperature creep resistance of rare earth magnesium alloys by pre-deforming the abnormal twinning control structure Methods. It belongs to the technical field of non-ferrous metal material failure and protection. Background technique [0002] Rare earth magnesium alloys (Mg-RE alloys) have the advantages of low density, high specific strength and stiffness, rich resources, etc., so they have increasingly wide application prospects in the fields of transportation, aerospace and other fields. In recent years, although the research on the strengthening and toughening of rare earth magnesium alloys has made great progress, its strength is comparable to that of aluminum alloys, but there is still a big gap in high-temperature creep resistance compared with aluminum alloys,...

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 Applications(China)
IPC IPC(8): C22F1/06C22C23/06
CPCC22C23/06C22F1/06
Inventor 杨续跃肖振宇张笃秀霍庆欢
Owner CENT SOUTH UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap