內(nèi)生相非晶復(fù)合材料制備與力學(xué)性能研究
發(fā)布時間：2018-07-17 14:54
【摘要】：本文在優(yōu)化成分和調(diào)整工藝的基礎(chǔ)上,通過銅模噴鑄法制備內(nèi)生相非晶復(fù)合材料,通過XRD分析,組織觀察,DSC熱分析以及TEM透射來分析內(nèi)生相非晶復(fù)合材料的物相組成、兩相結(jié)構(gòu)和成分;采用INSTRON5985型電子萬能試驗機以及分離式Hopkinson壓桿測試材料在不同應(yīng)變率以及不同直徑尺寸下的力學(xué)性能表現(xiàn),結(jié)合SEM掃描電鏡觀察材料的斷口形貌,以揭示內(nèi)生相非晶復(fù)合材料的變形機理。Ti48Zr20Nb12Cu5Be15內(nèi)生相非晶復(fù)合材料由非晶基體相和均勻分布在非晶基體上的β-Ti(Zr,Nb)晶態(tài)相組成,在準靜態(tài)和動態(tài)壓縮條件下均表現(xiàn)有明顯的應(yīng)變率硬化效應(yīng),在準靜態(tài)壓縮條件下試樣的抗壓強度和斷裂應(yīng)變在1780MPa和27%以上,試樣斷口上有大量的脈狀花樣,隨著應(yīng)變率的提高,大量剪切滑移臺階以及協(xié)調(diào)變形的出現(xiàn)是其抗壓強度和斷裂應(yīng)變增大的主要原因;動態(tài)壓縮條件下試樣的抗壓強度和斷裂應(yīng)變在1556MPa和16%以上,大面積的合金熔覆、合金碎化以及高應(yīng)變率剪切帶運動與變形速度的不匹配導(dǎo)致材料在動態(tài)加載條件下較準靜態(tài)條件下具有較低的強度和塑性;不同直徑試樣的準靜態(tài)壓縮測試表明該材料具有明顯的尺寸效應(yīng),隨著試樣直徑的減小,試樣的抗壓強度和斷裂應(yīng)變不斷增大,大量分布的剪切帶以及枝晶相的錯動是使小尺寸試樣具有高強度和塑性的主要原因。對不同Ag添加量的(Ti48Zr20Nb12Cu5Be15)100-xAgx內(nèi)生相非晶復(fù)合材料進行研究表明:Ag的添加能夠提高非晶形成能力,改變內(nèi)生相的形態(tài)、尺寸和成分,隨著Ag添加量的增加,內(nèi)生枝晶相的枝晶尺寸和體積分數(shù)減小。(Ti48Zr20Nb12Cu5Be15)97.5Ag2.5內(nèi)生相非晶復(fù)合材料在準靜態(tài)以及動態(tài)壓縮條件下具有比Ti48Zr20Nb12Cu5Be15內(nèi)生相非晶復(fù)合材料更高的力學(xué)性能,其中準靜態(tài)壓縮抗壓強度有18%-19.7%的提高,斷裂應(yīng)變有16.5%-21.2%的增加;動態(tài)壓縮條件下材料的強度和斷裂應(yīng)變也有很大幅度的提高。兩種成分的拉伸實驗表明:實驗過程中兩種成分的試樣均出現(xiàn)了頸縮現(xiàn)象,與Ti48Zr20Nb12Cu5Be15內(nèi)生相非晶復(fù)合材料微觀形貌相比,(Ti48Zr20Nb12Cu5Be15)97.5Ag2.5內(nèi)生相非晶復(fù)合材料拉伸斷口上纖維區(qū)和剪切唇區(qū)域的面積更大,纖維區(qū)韌窩的大小更加均一,并且韌窩的深度更大,因此后者具有更大的斷裂變形和斷后伸長率。對于內(nèi)生相非晶復(fù)合材料,內(nèi)生相的體積分數(shù),尺寸以及形態(tài)分布對材料的性能有重要的影響,只有含有最優(yōu)體積分數(shù)和尺寸分布配比的內(nèi)生枝晶相時,材料在受力時能夠產(chǎn)生足夠的剪切帶,并且剪切帶在運動中得到枝晶相的阻礙,才會增加材料的強度和塑性。在(Ti48Zr20Nb12Cu5Be15)97.5Ag2.5內(nèi)生相非晶復(fù)合材料中,枝晶相的體積分數(shù)和尺寸分別為78%和30um,均小于Ti48Zr20Nb12Cu5Be15內(nèi)生相非晶復(fù)合材料中85%和50um的體積分數(shù)和尺寸,過大的枝晶相體積分數(shù)以及熟化的枝晶相分布使得內(nèi)生相非晶復(fù)合材料中的枝晶相對剪切帶的形核數(shù)量以及對剪切帶擴展的阻礙作用沒有(Ti48Zr20Nb12Cu5Be15)97.5Ag2.5內(nèi)生相非晶復(fù)合材料中枝晶相的貢獻大,因此(Ti48Zr20Nb12Cu5Be15)97.5Ag2.內(nèi)生相非晶復(fù)合材料在不同應(yīng)變率以及拉伸條件下的力學(xué)性能均優(yōu)于Ti48Zr20Nb12Cu5Be15內(nèi)生相非晶復(fù)合材料。
[Abstract]:In this paper, on the basis of optimizing the composition and adjusting process, the amorphous composite was prepared by the copper mold casting method. The phase composition, two phase structure and composition of the endophytic amorphous composites were analyzed by XRD analysis, microstructure observation, DSC thermal analysis and TEM transmission. The INSTRON5985 type electronic universal testing machine and the separated Hopkinson were used. The mechanical properties of the material under different strain rates and different diameters were measured by the pressure bar, and the fracture morphology of the material was observed by SEM scanning electron microscope to reveal the deformation mechanism of the endophytic Amorphous Composites. The.Ti48Zr20Nb12Cu5Be15 endogenic amorphous matrix and the beta -Ti (Zr, Nb) distributed evenly on the amorphous matrix. Under the conditions of quasi-static and dynamic compression, the strain rate hardening effect is obvious. Under quasi static compression conditions, the compressive strength and the fracture strain are above 1780MPa and 27%. There are a large number of pulse patterns on the fracture surface of the sample. With the increase of strain rate, a large number of shear slip steps and the occurrence of coordinated deformation appear. It is the main reason for the increase of the compressive strength and fracture strain; the compressive strength and the fracture strain of the specimen under dynamic compression are more than 1556MPa and 16%, the large area alloy cladding, the alloy fragmentation and the mismatch between the movement and the deformation velocity of the high strain rate shear band lead to the material under the dynamic loading condition compared with the quasi static condition. Low strength and plasticity; the quasi-static compression test of specimens with different diameters shows that the material has obvious size effect. With the decrease of the diameter of the specimen, the compressive strength and fracture strain of the specimen are increasing. The main reason for the high strength and plasticity of small size specimen is that the bulk of the shear band and the dislocation of the dendrite phase are the main reason. The study on (Ti48Zr20Nb12Cu5Be15) 100-xAgx endophytic Amorphous Composites with the addition of Ag shows that the addition of Ag can improve the amorphous formation ability, change the morphology, size and composition of the endophytic phase, and decrease the dendrite size and volume fraction of the endogenous dendrite with the increase of Ag addition. (Ti48Zr20Nb12Cu5Be15) 97.5Ag2.5 endophytic amorphous The composites have higher mechanical properties than Ti48Zr20Nb12Cu5Be15 endogenetic Amorphous Composites under quasi static and dynamic compression conditions, in which the quasi-static compression compressive strength is increased by 18%-19.7%, and the fracture strain is increased by 16.5%-21.2%, and the strength and fracture strain of the materials are greatly improved under the dynamic compression condition. The tensile test of two components showed that the necking phenomenon occurred in all the two components in the experimental process. Compared with the micromorphology of the Ti48Zr20Nb12Cu5Be15 endogenic amorphous composite, the area of the fiber area and the shear lip area on the tensile fracture surface of the 97.5Ag2.5 endogenic amorphous composite was larger, and the dimple of the fiber region was larger. The smaller one is smaller, and the depth of the dimple is greater, so the latter has a larger fracture deformation and a postfracture elongation. For the endogenetic amorphous composite, the volume fraction, size and shape distribution of the endophytic phase have an important influence on the properties of the material, only when the intrinsic dendrite contains the optimal body integral number and the size distribution ratio. A sufficient shear band can be produced when the force is subjected to force, and the shear band is hindered by the dendrite phase in motion. The strength and plasticity of the material will be increased. In (Ti48Zr20Nb12Cu5Be15) 97.5Ag2.5, the volume fraction and size of the dendrite phase are 78% and 30um, respectively, less than the amorphous Ti48Zr20Nb12Cu5Be15 in the endophytic phase. The volume fraction and size of 85% and 50um in the composite, the excessive dendrite volume fraction and the ripening dendrite phase distribution make the dendrite nucleation number of the dendrites in the amorphous composite material and the hindering effect on the shear band expansion without (Ti48Zr20Nb12Cu5Be15) 97.5Ag2.5 endogenic Amorphous Composites. As a result, the mechanical properties of (Ti48Zr20Nb12Cu5Be15) 97.5Ag2. endogenic Amorphous Composites under different strain rates and tensile conditions are superior to those of Ti48Zr20Nb12Cu5Be15 endogenic Amorphous Composites.
【學(xué)位授予單位】：北京理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB33
本文編號：2130001
[Abstract]:In this paper, on the basis of optimizing the composition and adjusting process, the amorphous composite was prepared by the copper mold casting method. The phase composition, two phase structure and composition of the endophytic amorphous composites were analyzed by XRD analysis, microstructure observation, DSC thermal analysis and TEM transmission. The INSTRON5985 type electronic universal testing machine and the separated Hopkinson were used. The mechanical properties of the material under different strain rates and different diameters were measured by the pressure bar, and the fracture morphology of the material was observed by SEM scanning electron microscope to reveal the deformation mechanism of the endophytic Amorphous Composites. The.Ti48Zr20Nb12Cu5Be15 endogenic amorphous matrix and the beta -Ti (Zr, Nb) distributed evenly on the amorphous matrix. Under the conditions of quasi-static and dynamic compression, the strain rate hardening effect is obvious. Under quasi static compression conditions, the compressive strength and the fracture strain are above 1780MPa and 27%. There are a large number of pulse patterns on the fracture surface of the sample. With the increase of strain rate, a large number of shear slip steps and the occurrence of coordinated deformation appear. It is the main reason for the increase of the compressive strength and fracture strain; the compressive strength and the fracture strain of the specimen under dynamic compression are more than 1556MPa and 16%, the large area alloy cladding, the alloy fragmentation and the mismatch between the movement and the deformation velocity of the high strain rate shear band lead to the material under the dynamic loading condition compared with the quasi static condition. Low strength and plasticity; the quasi-static compression test of specimens with different diameters shows that the material has obvious size effect. With the decrease of the diameter of the specimen, the compressive strength and fracture strain of the specimen are increasing. The main reason for the high strength and plasticity of small size specimen is that the bulk of the shear band and the dislocation of the dendrite phase are the main reason. The study on (Ti48Zr20Nb12Cu5Be15) 100-xAgx endophytic Amorphous Composites with the addition of Ag shows that the addition of Ag can improve the amorphous formation ability, change the morphology, size and composition of the endophytic phase, and decrease the dendrite size and volume fraction of the endogenous dendrite with the increase of Ag addition. (Ti48Zr20Nb12Cu5Be15) 97.5Ag2.5 endophytic amorphous The composites have higher mechanical properties than Ti48Zr20Nb12Cu5Be15 endogenetic Amorphous Composites under quasi static and dynamic compression conditions, in which the quasi-static compression compressive strength is increased by 18%-19.7%, and the fracture strain is increased by 16.5%-21.2%, and the strength and fracture strain of the materials are greatly improved under the dynamic compression condition. The tensile test of two components showed that the necking phenomenon occurred in all the two components in the experimental process. Compared with the micromorphology of the Ti48Zr20Nb12Cu5Be15 endogenic amorphous composite, the area of the fiber area and the shear lip area on the tensile fracture surface of the 97.5Ag2.5 endogenic amorphous composite was larger, and the dimple of the fiber region was larger. The smaller one is smaller, and the depth of the dimple is greater, so the latter has a larger fracture deformation and a postfracture elongation. For the endogenetic amorphous composite, the volume fraction, size and shape distribution of the endophytic phase have an important influence on the properties of the material, only when the intrinsic dendrite contains the optimal body integral number and the size distribution ratio. A sufficient shear band can be produced when the force is subjected to force, and the shear band is hindered by the dendrite phase in motion. The strength and plasticity of the material will be increased. In (Ti48Zr20Nb12Cu5Be15) 97.5Ag2.5, the volume fraction and size of the dendrite phase are 78% and 30um, respectively, less than the amorphous Ti48Zr20Nb12Cu5Be15 in the endophytic phase. The volume fraction and size of 85% and 50um in the composite, the excessive dendrite volume fraction and the ripening dendrite phase distribution make the dendrite nucleation number of the dendrites in the amorphous composite material and the hindering effect on the shear band expansion without (Ti48Zr20Nb12Cu5Be15) 97.5Ag2.5 endogenic Amorphous Composites. As a result, the mechanical properties of (Ti48Zr20Nb12Cu5Be15) 97.5Ag2. endogenic Amorphous Composites under different strain rates and tensile conditions are superior to those of Ti48Zr20Nb12Cu5Be15 endogenic Amorphous Composites.
【學(xué)位授予單位】：北京理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB33
【相似文獻】
相關(guān)碩士學(xué)位論文 前2條
1 沈永華;內(nèi)生相非晶復(fù)合材料制備與力學(xué)性能研究[D];北京理工大學(xué);2015年
2 趙曉博;反相非水乳液法制備聚酰亞胺微球[D];太原理工大學(xué);2010年
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