| With the rapid advancement of science and technology,the automation system of industrial production is getting higher and higher,and the application of high-intelligence large-scale production equipment is more and more extensive,but the vibration generated during work will seriously affect the overall efficiency of production,and even affect the whole equipment.More seriously,it affects the development of enterprises and the advancement of national science and technology.Therefore,it is imperative for material research workers to find a functional material that not only has excellent mechanical properties,but also has reduced vibration and reduced noise.In this paper,Zn-27A1 alloys with different Mg and Cu contents were prepared,the mechanical properties,wear resistance and damping properties of alloys with different compositions under the same heat treatment conditions were studied and their variation with elements was obtained.Through analysis and discussion,The following important conclusions have been madeAfter the ingot is heat treated,the microstructure and structure are different due to the different composition of the alloy.On the one hand,a suitable heat treatment process can refine the grains of the Zn-Al alloy and uniformly structure.On the other hand,for the Zn-27Al-xMg alloy,not only the Al-rich phase and the eutectoid phase but also the magnesium phase are present in the microstructure.And as the Mg content increases,the number of magnesium phases increases first and then decreases,the distribution becomes tight and gradually dispersed by looseness.Zn-27Al-xCu alloy mainly consists of η-Zn and eutectoid phase(a’+η).With the increase of copper element,The number of η-Zn grain increases,and its distribution changes from a scattered snowflake to a cluster of dendrites,while the number of eutectoid phases(a’+η)decreases first and then increasesWhen adding magnesium to ZA27 alloy,magnesium can increase the hardness and room temperature tensile strength of the alloy and reduce the elongation of ZA27 alloy,but copper will reduce the hardness of ZA27 alloy and increase the tensile strength and elongation of the material.The hardness of Zn-27Al-xMg alloy increases first and then decreases with the increase of magnesium content,and the hardness of Zn-27Al-0.8Mg reaches the maximum,which is 108 N/mm2.The Zn-27Al-0.8Mg alloy also has a high tensile strength of 291.61 MPa.When less than 2.0wt.%of copper element is added to ZA27 alloy,the hardness of the alloy increases first and then decreases with the increase of copper element in Zn-27Al-xCu.Therefore,the hardness of Zn-27Al-1.2Cu is up to 30.3.N/mm2,but compared with the hardness of ZA27 alloy 33 N/mm2,it is still reduced,at the same time,the addition of copper can significantly improve the tensile strength of ZA27 alloy,with the increase of copper in Zn-27Al-xCu,the tensile strength is gradually decreased,and the elongation is gradually increased.Zn-27Al-0.4Cu has a large tensile strength of 292.58 MPa,and Zn-27Al-2Cu has a large elongation of 80%.The friction coefficient of the ZA27 alloy was 0.58 at room temperature.When the addition of magnesium to ZA27,the friction coefficient of Zn-27Al-xMg decreased significantly,and with the increase of magnesium content,the wear resistance of the alloy increased first and then decreased,and the friction coefficient of Zn-27Al-0.8Mg was 0.28.For Zn-27Al-xCu,with the increase of the amount of copper added,the friction coefficient does not change significantly,that is,the wear resistance does not change significantly.At 100℃,the friction coefficient of ZA27 alloy is 0.63.Both magnesium and copper can improve the high temperature wear resistance of ZA27 alloy.Zn-27Al-1.6Mg and Zn-27Al-2Cu have the best wear resistance.The coefficient of friction is 0.34.The internal friction of the ZA27 alloy is 4.43×10-3.When less than 2,0 wt.%of magnesium or copper is added to the ZA27 alloy,the damping properties of the ZA27 alloy can be significantly improved.When the magnesium content in Zn-27Al-xMg is 0.8wt.%,the internal friction value is the largest,Q-1=5.61×10-3,and the internal friction value is increased by 27%at the most.When the addition amount of copper is 0.4wt.%,the internal consumption value of Zn-27Al-0.4Cu is the largest,which is 6.15 × 10-3,and the internal friction value is increased by 39%.Considering the mechanical properties,wear resistance and damping properties of the above eleven different alloys,the results show that the mechanical properties,wear resistance and damping properties of Zn-27Al-xMg alloys are significantly improved compared with ZA27 alloys.The tensile properties and damping properties of Zn-27Al-xCu alloys are obviously improved,but the hardness and wear resistance of the alloys are not satisfactory.Therefore,considering the excellent performance of Zn-27Al-xMg,it can be used as a new damping alloy in application and production.Among the Zn-27Al-xMg series alloys,Zn-27Al-0.8Mg has the best comprehensive performance. |
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