CN-117431449-B - Precipitation phase reinforced multi-principal element alloy and preparation method thereof

Abstract

The invention discloses a precipitation phase reinforced multi-principal element alloy and a preparation method thereof, the multi-principal element alloy is composed of at least three elements of tungsten, chromium, vanadium and iron, and has a tungsten-rich BCC structure precipitation strengthening phase. The precipitation-phase-strengthened multi-principal element alloy has high strength, high hardness and excellent plasticity.

Inventors

• CHEN SHUNHUA
• LIU CANFENG
• WU YUCHENG
• LI CHONG
• ZHANG JUNSHENG

Assignees

• 合肥工业大学

Dates

Publication Date

20260512

Application Date

20231027

Claims (3)

1. 1. A precipitation-strengthened multi-element alloy is characterized by having a precipitation-strengthened phase with a tungsten-rich BCC structure, wherein the multi-element alloy is composed of four elements of tungsten, chromium, vanadium and iron, the atomic ratios of the chromium, vanadium and iron are equal, and the atomic ratio of the tungsten element is 15 at-20 at%.
2. 2. The precipitation-strengthened multi-principal alloy of claim 1, wherein the multi-principal alloy has a yield strength of > 1200 MPa, a Vickers hardness of >700 kgf/mm 2 , and a fracture plasticity of >25%.
3. 3. A method for preparing the multi-principal element alloy according to any one of claims 1 to 2, comprising the steps of: step 1, taking tungsten, chromium, vanadium and iron as metal raw materials, removing an oxide layer on the surface of the metal, ultrasonically cleaning, drying, and weighing according to a proportion; Step 2, placing the prepared metal raw materials into a crucible of vacuum arc melting equipment according to the sequence of low-melting point elements below and high-melting point elements above, vacuumizing the equipment, and then filling argon as shielding gas; step 3, smelting the alloy ingot for 2min to consume residual oxygen in the furnace before smelting the alloy ingot, then moving a smelting gun to an alloy ingot crucible to smelt the alloy ingot with the current of 240-300A, turning over the alloy ingot and depending on the inner wall of the crucible after each smelting, smelting from the top of the alloy ingot to the bottom of the crucible after the next smelting, and ensuring that the alloy smelting is uniform, thus finally obtaining the FeVCrW-series multi-main-element alloy ingot.

Description

Precipitation phase reinforced multi-principal element alloy and preparation method thereof Technical Field The invention relates to the technical field of advanced metal preparation, in particular to a precipitation phase reinforced multi-principal element alloy and a preparation method thereof. Background The traditional alloy mainly takes one to two metal elements as principal components, and optimizes the performance of the alloy by regulating and controlling microelements. In recent years, multi-principal element alloys generally contain three or more elements, each of which is principal element, and have been attracting attention due to their excellent mechanical properties. Due to serious lattice distortion effect and cocktail effect, the multi-principal element alloy with principal elements being refractory elements can show excellent strength and high-temperature performance, and has good engineering application prospect. With the development of new generation technology in China, the requirements of high-end equipment on material performance are further improved. Under the condition that the traditional nickel-based superalloy can not meet the requirement of the aerospace field on high-temperature resistant materials, the multi-principal-element alloy with excellent research and development performance and novel principal elements being refractory elements has important significance for industry development. At present, the mechanical properties of multi-principal element alloys have a trade-off effect, namely, the alloys are difficult to obtain higher strength and excellent plasticity at the same time. Therefore, the design and preparation of multi-principal element alloys with high strength, high hardness and excellent plasticity remain very challenging. Disclosure of Invention Based on the problems existing in the prior art, the invention provides a precipitation phase reinforced multi-principal element alloy and a preparation method thereof, and aims to ensure that the obtained multi-principal element alloy has high strength, high hardness and better plasticity. The invention adopts the following technical scheme for realizing the purpose: A precipitation-strengthened multi-element alloy is characterized in that the multi-element alloy is composed of at least three elements of tungsten, chromium, vanadium and iron, has a tungsten-rich BCC structure (system cube structure), precipitates a strengthening phase, and has high strength (yield strength >1200 MPa), high hardness (Vickers hardness >700kgf/mm 2) and excellent plasticity (fracture plasticity > 25%). Preferably, a multi-principal component alloy system with enhanced precipitation phases is FeVCrW, so as to obtain a dendrite structure with element segregation, and enable the alloy to have excellent plasticity. Further, in order to obtain a precipitation-strengthened phase, the invention utilizes an in-situ generation method to increase the content of dendrites or elements enriched among dendrites so as to obtain the precipitation-strengthened phase. Preferably, the element regulated and controlled by the invention is W element, and other principal elements have element contents with equal atomic ratio so as to obtain a precipitation strengthening phase of a hard tungsten-rich BCC structure, so that the alloy has high strength and high hardness. The atomic ratio of tungsten element is 15at.% to 20at.%. The preparation method of the precipitation phase reinforced multi-principal element alloy comprises the following steps: step 1, taking tungsten, chromium, vanadium and iron with the purity of 99.9wt.% as metal raw materials, removing an oxide layer on the surface of the metal, carrying out ultrasonic cleaning and drying, weighing according to a proportion, and accurately obtaining the mass of +/-0.001 g; Step 2, placing the prepared metal raw materials into a crucible of vacuum arc melting equipment according to the sequence of low-melting point elements below and high-melting point elements above, vacuumizing the equipment, and then filling argon as shielding gas; And 3, smelting the titanium ingot for 2 minutes to consume residual oxygen in the furnace before smelting the alloy ingot, and then moving a smelting gun to an alloy ingot crucible to smelt the alloy ingot, wherein the current is 240-300A. After each smelting, the alloy ingot is turned over and depends on the inner wall of the crucible, and the next smelting is performed to slowly smelt from the top of the alloy ingot, so that alloy liquid flows to the bottom of the crucible, and the alloy smelting uniformity is ensured. Finally obtaining FeVCrW series multi-principal element alloy ingots. The beneficial effects of the invention are as follows: 1. The multi-principal element alloy with the tungsten-rich BCC structure precipitation phase strengthening provided by the invention has high strength, high hardness and good plasticity, and has excellent comprehensive mechanical propert