Mn對(duì)Mg-5Sn-2Al-Zn變形合金組織演變及力學(xué)性能的影響
發(fā)布時(shí)間：2019-03-25 19:40
【摘要】：本文利用純鎂錠、錫錠,純鋁粒、鋅粒及含錳10%的鎂-錳中間合金,在實(shí)驗(yàn)室條件下完成Mg-5Sn-2Al-Zn-xMn(x=0、0.2、0.5及0.8)合金的制備。因?yàn)楹辖鹪跐茶T時(shí)結(jié)晶較快,得到非平衡組織,存在嚴(yán)重的成分偏析。為了平衡組織、均勻成分,也為后續(xù)塑性變形做準(zhǔn)備,必須對(duì)合金采取固溶處理。通過(guò)X射線衍射儀(XRD)進(jìn)行物相分析,采用光學(xué)顯微鏡、掃描電子顯微鏡(SEM)輔以能譜儀(EDS)以及透射電鏡(TEM)對(duì)不同Mn含量的Mg-5Sn-2Al-Zn(TAZ521)合金進(jìn)行微觀組織分析,利用萬(wàn)能壓縮機(jī)對(duì)以上合金進(jìn)行室溫抗壓強(qiáng)度測(cè)試,用維氏硬度儀對(duì)合金進(jìn)行表面硬度測(cè)試,研究不同Mn含量對(duì)合金鑄態(tài)、固溶后組織及力學(xué)性能的影響。在熱模擬壓力機(jī)上采取不同的變形溫度和變形速率,對(duì)經(jīng)過(guò)均勻化處理的TAZ521-xMn(x=0、0.2、0.5及0.8)鎂合金進(jìn)行熱變形實(shí)驗(yàn),分析了變形溫度、變形速率對(duì)熱壓縮變形過(guò)程流變應(yīng)力的影響,并建立了TAZ521鎂合金高溫變形時(shí)的應(yīng)力-應(yīng)變關(guān)系模型。同時(shí)分析了Mn的加入對(duì)TAZ521合金高溫變形應(yīng)力及動(dòng)態(tài)再結(jié)晶組織的影響。分析結(jié)果表明:TAZ521合金組織主要由α-Mg相、Mg2Sn相以及較少量的β-Mg17Al12相組成;Mn含量的增加促進(jìn)了Mg2Sn相和β-Mg17Al12相在枝晶間的析出分布,并使枝晶細(xì)化。在含有Mn的TAZ521固溶態(tài)合金中彌散分布著一定數(shù)量的Al-Mn相,主要以顆粒狀的Al8Mn5相和細(xì)長(zhǎng)桿狀的Al11Mn4相存在,一些細(xì)小的顆粒狀或塊狀A(yù)l-Mn相作為異質(zhì)形核的核心,分布于原始晶界處。對(duì)不同Mn含量的TAZ521合金進(jìn)行室溫壓縮實(shí)驗(yàn),當(dāng)Mn含量在0.2%和0.5%時(shí)室溫力學(xué)性能較好,當(dāng)含Mn達(dá)到0.8%時(shí),顆粒狀的第二相分布明顯增多,其力學(xué)性能也急劇下降。隨著Mn含量的增加,TAZ521合金的硬度總體呈現(xiàn)一定程度的上升趨勢(shì),但提高幅度不大。當(dāng)Mn含量從0.2%提高到0.5%時(shí),TAZ521合金硬度有小幅提高,而繼續(xù)增加到0.8%時(shí),改善效果則不夠顯著。Mn的添加使得TAZ521合金在熱變形下的流變應(yīng)力顯著降低,并且在保持較高的溫度條件下,變形速率越低,應(yīng)力的降低效果越顯著。少量的Mn也可以促進(jìn)TAZ521合金在高溫變形下的動(dòng)態(tài)再結(jié)晶形核,隨著Mn含量的逐漸增加,對(duì)TAZ521鎂合金再結(jié)晶促進(jìn)效果更加明顯,因此Mn在TAZ521合金高溫塑性變形過(guò)程中可以起到一定細(xì)化晶粒的作用。
[Abstract]:In this paper, pure magnesium ingots, tin ingots, pure aluminum grains, zinc particles and magnesium-manganese master alloys containing 10% mn were used to prepare Mg-5Sn-2Al-Zn-xMn (x 0, 0.2, 0.5 and 0.8) alloys under laboratory conditions. Because the alloy crystallizes rapidly during casting, the non-equilibrium structure is obtained, and there is serious component segregation. In order to balance the microstructure, uniform composition, and prepare for the subsequent plastic deformation, the alloy must be treated with solid solution. Phase analysis was carried out by X-ray diffractometer (XRD), and optical microscope was used. The microstructure of Mg-5Sn-2Al-Zn (TAZ521) alloy with different Mn content was analyzed by scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The compressive strength of the above alloys at room temperature was measured by universal compressor, and the surface hardness of the alloys was tested by Vickers hardness instrument. The effects of different Mn content on the as-cast, solid solution microstructure and mechanical properties of the alloys were studied. The deformation temperature of TAZ521-xMn (x 0, 0. 2, 0. 5 and 0. 8) magnesium alloy treated by homogenization was studied by using different deformation temperature and deformation rate in the thermal simulation pressure machine, the deformation temperature was analyzed, and the deformation temperature of magnesium alloy TAZ521-xMn (x 0, 0. 2, 0. 5 and 0. 8) The effect of deformation rate on the flow stress during hot compression deformation was studied. The stress-strain relationship model of TAZ521 magnesium alloy during high temperature deformation was established. The effects of the addition of Mn on the high temperature deformation stress and dynamic recrystallization microstructure of TAZ521 alloy were also analyzed. The results show that the microstructure of TAZ521 alloy is mainly composed of 偽-Mg phase, Mg2Sn phase and a small amount of 尾-Mg17Al12 phase, and the increase of Mn content promotes the precipitation and distribution of Mg2Sn phase and 尾-Mg17Al12 phase between dendrites, and refines the dendrite. In the TAZ521 solid solution alloy containing Mn, a certain number of Al-Mn phases are dispersed, mainly in granular Al8Mn5 phase and slender rod Al11Mn4 phase. Some fine granular or massive Al-Mn phases are the core of heterogeneous nucleation. Distributed at the original grain boundary. The mechanical properties of TAZ521 alloys with different Mn content were studied at room temperature. When the content of Mn was 0.2% and 0.5%, the mechanical properties at room temperature were better. When the content of Mn was 0.8%, the distribution of the second phase of particles increased obviously. Its mechanical properties also decreased sharply. With the increase of Mn content, the hardness of TAZ521 alloy increases to a certain extent, but the increase of hardness is not significant. When the content of Mn is increased from 0.2% to 0.5%, the hardness of TAZ521 alloy increases slightly, but when the content of mn increases to 0.8%, the improvement effect is not significant. The addition of mn makes the flow stress of TAZ521 alloy decrease significantly under hot deformation. Under the condition of high temperature, the lower the deformation rate, the more significant the effect of stress reduction. A small amount of Mn can also promote the dynamic recrystallization nucleation of TAZ521 alloy under high temperature deformation. With the increasing of Mn content, the effect of promoting recrystallization of TAZ521 magnesium alloy is more obvious. Therefore, Mn can play a role of grain refinement in the process of high temperature plastic deformation of TAZ521 alloy.
【學(xué)位授予單位】：沈陽(yáng)理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TG146.22
本文編號(hào)：2447256
[Abstract]:In this paper, pure magnesium ingots, tin ingots, pure aluminum grains, zinc particles and magnesium-manganese master alloys containing 10% mn were used to prepare Mg-5Sn-2Al-Zn-xMn (x 0, 0.2, 0.5 and 0.8) alloys under laboratory conditions. Because the alloy crystallizes rapidly during casting, the non-equilibrium structure is obtained, and there is serious component segregation. In order to balance the microstructure, uniform composition, and prepare for the subsequent plastic deformation, the alloy must be treated with solid solution. Phase analysis was carried out by X-ray diffractometer (XRD), and optical microscope was used. The microstructure of Mg-5Sn-2Al-Zn (TAZ521) alloy with different Mn content was analyzed by scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The compressive strength of the above alloys at room temperature was measured by universal compressor, and the surface hardness of the alloys was tested by Vickers hardness instrument. The effects of different Mn content on the as-cast, solid solution microstructure and mechanical properties of the alloys were studied. The deformation temperature of TAZ521-xMn (x 0, 0. 2, 0. 5 and 0. 8) magnesium alloy treated by homogenization was studied by using different deformation temperature and deformation rate in the thermal simulation pressure machine, the deformation temperature was analyzed, and the deformation temperature of magnesium alloy TAZ521-xMn (x 0, 0. 2, 0. 5 and 0. 8) The effect of deformation rate on the flow stress during hot compression deformation was studied. The stress-strain relationship model of TAZ521 magnesium alloy during high temperature deformation was established. The effects of the addition of Mn on the high temperature deformation stress and dynamic recrystallization microstructure of TAZ521 alloy were also analyzed. The results show that the microstructure of TAZ521 alloy is mainly composed of 偽-Mg phase, Mg2Sn phase and a small amount of 尾-Mg17Al12 phase, and the increase of Mn content promotes the precipitation and distribution of Mg2Sn phase and 尾-Mg17Al12 phase between dendrites, and refines the dendrite. In the TAZ521 solid solution alloy containing Mn, a certain number of Al-Mn phases are dispersed, mainly in granular Al8Mn5 phase and slender rod Al11Mn4 phase. Some fine granular or massive Al-Mn phases are the core of heterogeneous nucleation. Distributed at the original grain boundary. The mechanical properties of TAZ521 alloys with different Mn content were studied at room temperature. When the content of Mn was 0.2% and 0.5%, the mechanical properties at room temperature were better. When the content of Mn was 0.8%, the distribution of the second phase of particles increased obviously. Its mechanical properties also decreased sharply. With the increase of Mn content, the hardness of TAZ521 alloy increases to a certain extent, but the increase of hardness is not significant. When the content of Mn is increased from 0.2% to 0.5%, the hardness of TAZ521 alloy increases slightly, but when the content of mn increases to 0.8%, the improvement effect is not significant. The addition of mn makes the flow stress of TAZ521 alloy decrease significantly under hot deformation. Under the condition of high temperature, the lower the deformation rate, the more significant the effect of stress reduction. A small amount of Mn can also promote the dynamic recrystallization nucleation of TAZ521 alloy under high temperature deformation. With the increasing of Mn content, the effect of promoting recrystallization of TAZ521 magnesium alloy is more obvious. Therefore, Mn can play a role of grain refinement in the process of high temperature plastic deformation of TAZ521 alloy.
【學(xué)位授予單位】：沈陽(yáng)理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TG146.22
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 張敏剛;郝建強(qiáng);羅小萍;周俊琪;柴躍生;;新型Mg-Sn-Y-Zr鎂合金熱壓縮行為的研究[J];熱加工工藝;2016年06期
2 張薇;金培鵬;王金輝;朱云鵬;;Mg-4Sn-2.5Pb鎂合金的熱變形行為[J];鑄造技術(shù);2015年12期
3 魯進(jìn)波;王靜鴿;王智民;;Mn、Re對(duì)AZ102鎂合金組織性能的影響[J];熱加工工藝;2015年16期
4 張保豐;張萍;陳小偉;王利國(guó);;AM60合金中Al-Mn相研究[J];鑄造;2014年07期
5 吳震;金培鵬;王金輝;唐彬彬;;Mg-Al-Mn系鎂合金中含Mn粒子的形貌和分布特征[J];鑄造技術(shù);2014年06期
6 田樹(shù)科;郭學(xué)鋒;;鑄態(tài)Mg-Sn-Al-Zn合金組織和力學(xué)性能[J];熱加工工藝;2014年04期
7 瞿祥落;韓寶;趙文博;許春香;;熱處理對(duì)Mg-7Sn-4Al-2Zn-xSr合金的組織演變和力學(xué)性能的影響[J];鑄造;2014年03期
8 張丁非;諶夏;潘復(fù)生;蔣璐瑤;胡光山;余大亮;;稀土元素對(duì)鎂合金力學(xué)性能影響的研究進(jìn)展[J];功能材料;2014年05期
9 馬磊娟;王磊;;基于Gleeble-1500熱模擬試驗(yàn)機(jī)的鎂合金AZ31B塑性變形研究[J];鑄造技術(shù);2013年12期
10 朱蜜;龔佳;王少華;孫燦;郭興伍;;Mn對(duì)Mg-9Al-2Sn鎂合金耐蝕性能的影響[J];腐蝕科學(xué)與防護(hù)技術(shù);2013年06期
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