CN105568017A - Nanoscale molybdenum disilicide modified Mg-Al-Si based magnesium alloy material for casting automobile parts and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of preparation of magnesium alloy, in particular to a nanoscale molybdenum disilicide modified Mg-Al-Si based magnesium alloy material for casting automobile parts and a preparation method thereof. The material is Mg-Al-Si based high-heat-resistance alloy and doped with elements such as Ca, Pr and nanoscale zirconium powder, thereby having a more excellent comprehensive mechanical property. Besides, a polyvinylpyrrolidone absolute ethyl alcohol solution is used as a medium, nanoscale molybdenum disilicide is scattered in the solution, and the mixture and Mg powder are mixed and ground, so that the nanoscale molybdenum disilicide is evenly wrapped and scattered in the Mg powder and is mixed with other metal elements more sufficiently in the later smelting process. The mode has a better modification effect compared with the direct blending mode, and the prepared magnesium alloy is compact in texture, excellent in high temperature resistance, high in intensity and resistant to both abrasion and corrosion; the machinability and usability of automobile parts prepared from the material are both improved.

Description

Mg-Al-Si series magnesium alloy material of a kind of nanometer molybdenum disilicide modification for 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 Mg-Al-Si series magnesium alloy material of a kind of nanometer molybdenum disilicide modification for 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 Mg-Al-Si series magnesium alloy material of a kind of nanometer molybdenum disilicide modification for 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-Si series magnesium alloy material of the nanometer molybdenum disilicide modification for 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 4-6wt.%, Si powder 2-3wt.%, Ca powder 1-2wt.%, Pr powder 1-1.5wt.%, nanometer zirconium powder 0.4-0.5wt.%, nanometer molybdenum disilicide 1-1.5wt.%, polyvinylpyrrolidone 0.01-0.02wt.%, dehydrated alcohol are appropriate, impurity element≤0.01wt.%, surplus are Mg powder.

The preparation method of the Mg-Al-Si series magnesium alloy material of described a kind of nanometer molybdenum disilicide modification for casting of automobile component is:

(1) first polyvinylpyrrolidone is dropped in appropriate dehydrated alcohol, be mixed with polyvinylpyrrolidone dehydrated alcohol, drop into nanometer molybdenum disilicide subsequently, high-speed stirring dispersion makes nanometer molybdenum disilicide 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-Si system, and the Ca of blending wherein, the element such as Pr and nano level zirconium powder, obtain the material that comprehensive mechanical property is more excellent, in addition, using polyvinylpyrrolidone ethanol solution as medium, nanometer molybdenum disilicide is scattered in wherein, again by itself and Mg powder mixed grinding, nanometer molybdenum disilicide is evenly wrapped up and is scattered in Mg powder, what mix with other metallic element in follow-up fusion process is also more abundant, mode modified effect than direct blending is better, the Magnesium Alloy of preparation is tight, high thermal resistance is splendid, intensity is high, wear-and corrosion-resistant, 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.%, Si powder 3wt.%, Ca powder 1.5wt.%, Pr powder 1wt.%, nanometer zirconium powder 0.4wt.%, nanometer molybdenum disilicide 1.0wt.%, 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 nanometer molybdenum disilicide subsequently, high-speed stirring dispersion makes nanometer molybdenum disilicide be uniformly dispersed completely in the solution, drop into Mg powder subsequently, after continuing dispersed with stirring 20min, 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 725 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: 326.5MPa, unit elongation: 14.3%, hardness: 142HV, under 200 DEG C of conditions, tensile strength reaches 312MPa, unit elongation is 11.4%, and the more congener ordinary magnesium alloy of wear resistance improves 62.6%.

Claims (2)

1. the Mg-Al-Si series magnesium alloy material for the nanometer molybdenum disilicide modification 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 4-6wt.%, Si powder 2-3wt.%, Ca powder 1-2wt.%, Pr powder 1-1.5wt.%, nanometer zirconium powder 0.4-0.5wt.%, nanometer molybdenum disilicide 1-1.5wt.%, polyvinylpyrrolidone 0.01-0.02wt.%, dehydrated alcohol are appropriate, impurity element≤0.01wt.%, surplus are Mg powder.

2. the preparation method of the Mg-Al-Si series magnesium alloy material of a kind of nanometer molybdenum disilicide modification for 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 nanometer molybdenum disilicide subsequently, high-speed stirring dispersion makes nanometer molybdenum disilicide 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.