發(fā)布時(shí)間：2018-03-06 11:34

  本文選題：磨料水射流車削　切入點(diǎn)：高速?zèng)_擊響應(yīng)　出處：《山東大學(xué)》2016年博士論文　論文類型：學(xué)位論文

【摘要】：針對(duì)現(xiàn)有磨料水射流車削研究中存在諸如硬脆材料車削性能和車削機(jī)理研究較少、車削性能模型不具有通用性、車削工藝參數(shù)多目標(biāo)優(yōu)化模型欠缺等問題,本文主要研究了磨粒高速?zèng)_擊陶瓷的響應(yīng)和磨料水射流車削工藝參數(shù)優(yōu)化。實(shí)驗(yàn)研究了磨料水射流的車削性能,揭示了車削工藝參數(shù)對(duì)車削性能的影響。研究了磨料粒子高速?zèng)_擊氧化鋁陶瓷的響應(yīng),揭示了材料沖擊過程的微觀機(jī)理。建立了基于有限元法的磨料水射流車削陶瓷的切除深度通用模型,研究了車削工藝參數(shù)及其交互作用對(duì)切除深度和表面粗糙度的影響,解決了徑向模式車削中難以控制切除深度的難題。建立了磨料水射流車削陶瓷的工藝參數(shù)優(yōu)化模型。這些研究成果將為徑向模式磨料水射流車削陶瓷等硬脆材料提供重要的理論基礎(chǔ)和技術(shù)保障。實(shí)驗(yàn)研究了磨料水射流車削氧化鋁陶瓷的主要工藝參數(shù)對(duì)材料切除深度和材料去除率的影響。結(jié)果表明,噴嘴橫向移動(dòng)速度和水射流壓強(qiáng)對(duì)切除深度和材料去除率的影響較大,靶距和工件表面線速度對(duì)切除深度和材料去除率的影響較小；研究了磨料水射流車削氧化鋁陶瓷的材料去除機(jī)理。結(jié)果表明,以較小的噴嘴傾斜角度車削時(shí),陶瓷的主要去除機(jī)理是塑性剪切,以較大的噴嘴傾斜角度來車削時(shí),陶瓷的主要去除機(jī)理是脆性斷裂。研究了磨料粒子高速?zèng)_擊氧化鋁陶瓷時(shí)的沖擊響應(yīng)。建立了三維單顆磨料粒子沖擊氧化鋁陶瓷的有限元模型。基于有限元模型獲得了磨料粒子的沖擊動(dòng)能效率。結(jié)果表明,磨料粒子的沖擊動(dòng)能效率隨著沖擊速度、噴嘴傾斜角度和磨粒尺寸的增加而增大,磨料粒子的沖擊動(dòng)能效率越大,表明磨料粒子的沖擊能力越強(qiáng)；通過有限元模型分析了不同沖擊速度和不同噴嘴傾斜角度下,靶材在不同時(shí)刻的應(yīng)力分布。沖擊后的靶材表面單元受壓應(yīng)力,非沖擊表面單元受拉應(yīng)力；研究了不同形狀磨料粒子高速?zèng)_擊氧化鋁陶瓷的響應(yīng)。結(jié)果表明,球形和圓錐形磨料粒子的沖擊動(dòng)能效率較高,沖蝕凹坑體積和深度較大。立方體形和圓柱體形磨料粒子的沖擊動(dòng)能效率較低,沖蝕凹坑體積和深度較小。磨料粒子形狀對(duì)沖蝕凹坑體積、凹坑深度和沖擊動(dòng)能效率三者的影響趨勢(shì)一致；建立的三維磨料粒子高速?zèng)_擊氧化鋁陶瓷的有限元模型能較好地預(yù)測(cè)沖蝕凹坑體積和沖蝕凹坑深度。結(jié)果表明,不同沖擊速度、不同噴嘴傾斜角度和不同磨料尺寸下的沖蝕凹坑體積和沖蝕凹坑深度的預(yù)測(cè)值與實(shí)驗(yàn)值基本吻合。研究了單顆磨料粒子高速?zèng)_擊陶瓷的微觀去除機(jī)理。結(jié)果表明,其主要去除機(jī)理是裂紋分叉和聚合以及微孔洞；研究了不同排布的四顆磨料粒子高速?zèng)_擊陶瓷的沖擊響應(yīng)。結(jié)果表明,四顆磨料粒子高速?zèng)_擊氧化鋁陶瓷時(shí),磨料粒子產(chǎn)生的應(yīng)力波疊加和耦合作用是陶瓷表面材料大范圍去除的主要機(jī)理；建立了磨料水射流車削氧化鋁陶瓷的切除深度通用模型。切除深度預(yù)測(cè)值與實(shí)驗(yàn)值具有較好的一致性,兩者之間的平均相對(duì)誤差小于15%。利用響應(yīng)曲面法研究了磨料水射流車削氧化鋁陶瓷的工藝參數(shù)建模和優(yōu)化。研究了磨料水射流工藝參數(shù)之間的交互作用對(duì)切除深度和表面粗糙度的影響。結(jié)果表明,在較小的噴嘴橫向移動(dòng)速度和較大的水射流壓強(qiáng)條件、較小的噴嘴橫向移動(dòng)速度和較大的磨料流量條件,或較小的噴嘴橫向移動(dòng)速度和較大的靶距條件時(shí),切除深度最大。由于二次方效應(yīng),當(dāng)水射流壓強(qiáng)和磨料流量都取中間值時(shí),表面粗糙度最小。噴嘴橫向移動(dòng)速度和磨料流量之間的交互作用對(duì)切除深度和表面粗糙度的影響較大；利用期望度函數(shù)響應(yīng)曲面法研究了獲得期望切除深度和表面粗糙度時(shí)的工藝參數(shù)優(yōu)化。結(jié)果表明,在第一套準(zhǔn)則優(yōu)化的工藝參數(shù)下獲得的最大切除深度為480μm,表面粗糙度為10.3μm。在第二套準(zhǔn)則優(yōu)化的工藝參數(shù)下獲得的最大切除深度為390μm,最小表面粗糙度為5.3μm。實(shí)驗(yàn)驗(yàn)證了工藝參數(shù)優(yōu)化結(jié)果的有效性。
[Abstract]:Aiming at the problems such as hard and brittle materials turning performance and cutting mechanism of abrasive water jet cutting of the existing research, turning performance model is not universal, a multi-objective optimization model of turning process parameters such as lack of problem, this paper mainly studies the impact of high speed abrasive ceramic ring and abrasive water jet cutting process parameters were experimentally investigated. The machinability of abrasive water jet, reveals the influence of process parameters on the performance of the lathe turning. The response of abrasive particles in high speed impact of alumina ceramic materials, the micro mechanism of impact process was revealed. A general model of resection depth of the finite element method of abrasive water jet based on ceramic turning, turning process parameters and their interactions the ablation depth and surface roughness effects, and solve the difficult problem of the control of cutting depth. The radial mode in turning abrasive water Parameter optimization model of jet turning ceramic. These research results will provide technical support and theoretical basis for hard brittle materials with abrasive water jet cutting ceramic radial mode. The main parameters influencing experimental study on abrasive water jet cutting of alumina ceramic material removal depth and material removal rate. The results show that the influence of lateral nozzle the moving speed and water jet pressure on the cutting depth and the material removal rate is larger, smaller effects of target distance and surface line speed on the cutting depth and the material removal rate; removal mechanism of abrasive water jet cutting of alumina ceramic materials. The results show that the nozzle with smaller inclination angle when turning, the main mechanism of the removal of ceramic is the plastic shear, to turning to larger nozzle inclination angle, the main mechanism of the removal of ceramic is brittle fracture of high speed abrasive particles. The impact of the shock response of alumina ceramics. To establish a three-dimensional finite element of single abrasive particle impact of alumina ceramic model. Based on the finite element model of the impact energy efficiency of abrasive particles. The results show that the impact energy efficiency of abrasive particles with increasing impact velocity, nozzle inclination angle and the grain size increases, the impact kinetic energy the greater the efficiency of abrasive particles, abrasive particles that impact ability is stronger; the finite element model to analyze the impact of different velocity and different nozzle inclination angle, the stress distribution of the target at different time. The stress surface of a target unit compression after impact and non impact surface unit tensile stress on the response of different; the shape of abrasive particles in high speed impact of alumina ceramics. The results show that the impact energy efficiency high spherical and conical abrasive particles, the erosion pit depth and volume larger. The impact energy efficiency and cylindrical shape of abrasive particles is low, erosion pit depth and volume is small. The volume of abrasive particle shape on the erosion pits, pit depth and the influence of the three impact energy efficiency; three-dimensional finite element model of abrasive particles in high-speed impact of alumina ceramics established can better predict the erosion volume and the erosion pits pit depth. The results show that different impact velocity, different nozzle inclination angle and different size abrasive erosion pit volume and erosion pit depth values coincide with the experimental values. The microscopic mechanism of single abrasive particle impacting ceramic removal. The results showed that the main removal mechanism is crack bifurcation and polymerization and microporous four abrasive particle hole; high speed impact ceramic impact response of different arrangement. The results showed that four of abrasive particles at high speed On alumina ceramic, abrasive particles produced by stress wave superposition and coupling effect is the main mechanism of material removal of a wide range of ceramic surface; a general model of abrasive water jet depth for turning alumina ceramics. Resection depth prediction value has a good agreement with the experimental data, the average relative error between them is less than 15%. by modeling and optimization of process parameters of abrasive water jet cutting of alumina ceramics by response surface methodology. Studies the interaction between abrasive water jet parameters on ablation depth and surface roughness effects. The results show that the nozzle traverse speed of smaller and larger water jet pressure conditions, the smaller the nozzle moving speed and lateral the larger or smaller abrasive flow conditions, the nozzle moving speed of horizontal and larger target distance conditions, the maximum depth of resection due to two side effects. When the water jet pressure, abrasive flow rate and has the intermediate value, minimum surface roughness. Between the nozzle traverse speed and abrasive flow interaction on the ablation depth and surface roughness of the larger; with the expectation degree function of the desired resection depth and surface roughness parameter optimization by response surface method. The results show that the gain in the first set of criteria for the optimization of process parameters of the maximum ablation depth was 480 m, the surface roughness of 10.3 M. in the second set of criteria for the optimization of process parameters of the maximum ablation depth was 390 m, the surface roughness of 5.3 M. experiments to validate the optimization results the process parameters.

【學(xué)位授予單位】：山東大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：TG664;TQ174.6
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本文編號(hào)：1574668