CN105256210A - Nano silicon nitride-zirconium oxide hybrid modifying Mg-Al-Zn magnesium alloy material for casting automobile parts and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of magnesium alloy preparation, in particular to a nano silicon nitride-zirconium oxide hybrid modifying Mg-Al-Zn magnesium alloy material for casting automobile parts and a preparation method thereof. The material belongs to Mg-Al-Zn high-heat-resistance alloy and has an excellent mechanical property, heat resistance and high temperature creep resistance. A polyvinylpyrrolidone absolute ethyl alcohol solution is used as a medium, and nano zirconium oxide and nano silicon nitride are scattered into the solution and then are mixed and ground with Mg powder; nano composite powder is evenly wrapped and scattered into the Mg powder and is mixed with other metallic elements more fully in the subsequent melting process, and an efficient and stable modification effect is achieved. In the melting process of the prepared magnesium alloy material, grains precipitate out in a smaller form at a higher speed, and the material is excellent in comprehensive mechanical property, good in heat resistance and corrosion resistance, light and efficient. The machinability and using performance of the automobile parts prepared from the material are both improved.

Description

A kind of Mg-Al-Zn series magnesium alloy material mixed and modified for the nano-silicon nitride-zirconium white of casting of automobile component and preparation method thereof

Technical field

The present invention relates to magnesium alloy materials preparing technical field, be specifically related to a kind of Mg-Al-Zn series magnesium alloy material mixed and modified for the nano-silicon nitride-zirconium white of casting of automobile component and preparation method thereof.

Background technology

It is comparatively extensive that magnesium alloy materials manufactures field application at automobile component, market demand also progressively rises, magnesium alloy materials has that mass density is little, damping property good, specific tenacity and specific rigidity is high, fusing point is low, good casting property, more utilize the advantages such as automotive light weight technology, although magnesium alloy materials possesses these advantages, but magnesium alloy materials application in the car is at present also very limited, causes the reason of this phenomenon to mainly contain: magnesium alloy exists high temperature creep difference, not environmental corrosion resisting; High-performance magnesium-alloy production cost is higher.

The kind of current magnesium alloy mainly contains Mg-Al-Zn system high-ductility alloy, Mg-Al system refractory alloy, Mg-Zn system refractory alloy and Mg-Zn-RE, Mg-RE etc. are several, wherein Mg-Al system refractory alloy most species, add the Mg-Al series alloy that different element proportionings can obtain different performance characteristics, no doubt there is its exclusive advantage in these alloy materials, also there are some defects, it is higher that existing problem mainly concentrates on production cost, the aspects such as material use efficiency is low, still be restricted in practical application, therefore, following research aspect mainly concentrates on and replaces rare earth element with other elements of part, to reduce the strengthening effect of production cost and more efficient comprehensive each element, suppress the detrimentally affect of single-element, improve the single mode of production, obtain the alloy material that over-all properties is more excellent.

Summary of the invention

In order to overcome the defect of prior art, the invention provides a kind of Mg-Al-Zn series magnesium alloy material mixed and modified for the nano-silicon nitride-zirconium white of casting of automobile component and preparation method thereof, to achieve these goals, the technical solution used in the present invention is as follows:

A kind of Mg-Al-Zn series magnesium alloy material mixed and modified for the nano-silicon nitride-zirconium white of casting of automobile component, it is characterized in that, this magnesium alloy materials is made up of the raw material of following weight percent: Al powder 5-6wt.%, Zn powder 2.5-3wt.%, Cr powder 0.1-0.2wt.%, Gd powder 1-1.5wt.%, nano zircite 0.4-0.5wt.%, nano-silicon nitride 1-2wt.%, polyvinylpyrrolidone 0.01-0.02wt.%, dehydrated alcohol are appropriate, impurity element≤0.01wt.%, surplus are Mg powder.

The preparation method of described a kind of mixed and modified for the nano-silicon nitride-zirconium white of casting of automobile component Mg-Al-Zn series magnesium alloy material is:

(1) first polyvinylpyrrolidone is dropped in appropriate dehydrated alcohol, be mixed with polyvinylpyrrolidone dehydrated alcohol, drop into nano zircite, nano-silicon nitride subsequently, high-speed stirring dispersion makes nano-powder be uniformly dispersed completely in the solution, drop into Mg powder subsequently, after continuing dispersed with stirring 20-30min, mixed slurry is dropped into grinding in ball grinder and stir 40-50min, finally by the process of gained slurry drying, remove dehydrated alcohol completely, gained mixed powder is for subsequent use, and wherein the volume ratio of dehydrated alcohol and Mg powder is 1-1.5:1;

(2) mixed powder that step (1) prepares is mixed with other leftover materials; fully be uniformly mixed in rear input resistance furnace; under shielding gas atmosphere, be heated to 700-750 DEG C while stirring carry out melting process; after the complete melting of material, 20-30min is placed in insulation; finally by the compression moulding of gained melt cast, to obtain final product.

Beneficial effect: the present invention has prepared the high refractory alloy of Mg-Al-Zn system, and the micro-Cr of blending wherein, Gd two kinds of elements, the mechanical property of alloy material and heat-resisting can be improved further, high temperature creep resistance, improve processing characteristics, in addition, using polyvinylpyrrolidone ethanol solution as medium, by nano zircite, nano-silicon nitride is scattered in wherein, again by itself and Mg powder mixed grinding, thus composite nano-powder is evenly wrapped up be scattered in Mg powder, what mix with other metallic element in follow-up fusion process is also more abundant, thus reach the modified effect of efficient stable, preparation magnesium alloy materials in fusion process crystal grain with more tiny form, speed is separated out faster, cast the material comprehensive mechanical property obtained excellent, thermotolerance and erosion resistance good, efficient and light weight, the automobile component processing characteristics prepared with this material and use properties all improve.

Embodiment

Embodiment

The magnesium alloy materials of the present embodiment is made up of the raw material of following weight part: Al powder 5.5wt.%, Zn powder 2.5wt.%, Cr powder 0.1wt.%, Gd powder 1.2wt.%, nano zircite 0.4wt.%, nano-silicon nitride 1.5wt.%, polyvinylpyrrolidone 0.01wt.%, dehydrated alcohol are appropriate, impurity element≤0.01wt.%, surplus are Mg powder.

Its preparation method is:

(1) first polyvinylpyrrolidone is dropped in appropriate dehydrated alcohol, be mixed with polyvinylpyrrolidone dehydrated alcohol, drop into nano zircite, nano-silicon nitride subsequently, high-speed stirring dispersion makes nano-powder be uniformly dispersed completely in the solution, drop into Mg powder subsequently, after continuing dispersed with stirring 25min, mixed slurry is dropped into grinding in ball grinder and stir 40min, finally by the process of gained slurry drying, remove dehydrated alcohol completely, gained mixed powder is for subsequent use, and wherein the volume ratio of dehydrated alcohol and Mg powder is 1.2:1;

(2) mixed powder that step (1) prepares is mixed with other leftover materials; fully be uniformly mixed in rear input resistance furnace; under shielding gas atmosphere, be heated to 730 DEG C while stirring carry out melting process; after the complete melting of material, 25min is placed in insulation; finally by the compression moulding of gained melt cast, to obtain final product.

The obtained magnesium alloy of the present embodiment is materialsed and is carried out the performance test results and be: the tensile strength under normal temperature: 323MPa, unit elongation: 12.1%, hardness: 135HV, under 200 DEG C of conditions, tensile strength reaches 300MPa, unit elongation is 8.8%, and the more congener ordinary magnesium alloy of wear resistance improves 62%.

Claims (2)

1. one kind for the mixed and modified Mg-Al-Zn series magnesium alloy material of the nano-silicon nitride-zirconium white of casting of automobile component, it is characterized in that, this magnesium alloy materials is made up of the raw material of following weight percent: Al powder 5-6wt.%, Zn powder 2.5-3wt.%, Cr powder 0.1-0.2wt.%, Gd powder 1-1.5wt.%, nano zircite 0.4-0.5wt.%, nano-silicon nitride 1-2wt.%, polyvinylpyrrolidone 0.01-0.02wt.%, dehydrated alcohol are appropriate, impurity element≤0.01wt.%, surplus are Mg powder.

2. the preparation method of a kind of Mg-Al-Zn series magnesium alloy material mixed and modified for the nano-silicon nitride-zirconium white of casting of automobile component as claimed in claim 1, it is characterized in that, described preparation method is:

(1) first polyvinylpyrrolidone is dropped in appropriate dehydrated alcohol, be mixed with polyvinylpyrrolidone dehydrated alcohol, drop into nano zircite, nano-silicon nitride subsequently, high-speed stirring dispersion makes nano-powder be uniformly dispersed completely in the solution, drop into Mg powder subsequently, after continuing dispersed with stirring 20-30min, mixed slurry is dropped into grinding in ball grinder and stir 40-50min, finally by the process of gained slurry drying, remove dehydrated alcohol completely, gained mixed powder is for subsequent use, and wherein the volume ratio of dehydrated alcohol and Mg powder is 1-1.5:1;

(2) mixed powder that step (1) prepares is mixed with other leftover materials; fully be uniformly mixed in rear input resistance furnace; under shielding gas atmosphere, be heated to 700-750 DEG C while stirring carry out melting process; after the complete melting of material, 20-30min is placed in insulation; finally by the compression moulding of gained melt cast, to obtain final product.