發(fā)布時間：2018-01-25 01:04

  本文關(guān)鍵詞： 碳纖維編織物 層狀陶瓷刀具 熱壓燒結(jié) 力學(xué)性能 微觀形貌 摩擦磨損性能　出處：《太原理工大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：高速切削技術(shù)加工效率與加工精度較高,在機械加工領(lǐng)域中扮演著極為重要的角色。高速切削技術(shù)對切削刀具的性能要求較高。目前,常用于高速切削加工的刀具有硬質(zhì)合金刀具、金屬陶瓷刀具、金剛石刀具、陶瓷刀具等,其中陶瓷刀具以其優(yōu)越的性能和較低的價格而受到廣泛的關(guān)注。然而陶瓷刀具韌性較低這一缺點嚴重制約了其進一步推廣與應(yīng)用。本文針對其缺點設(shè)計制備了碳纖維編織物增韌補強WC-TiC層狀復(fù)合陶瓷刀具材料。研究了TiC含量、燒結(jié)溫度、保溫時間對碳纖維編織物增韌補強WC-Ti C層狀復(fù)合陶瓷刀具材料力學(xué)性能和微觀組織的影響;分析了其增韌補強機理;研究了陶瓷刀具與難加工材料間的摩擦磨損性能。本課題提出了碳纖維編織物增韌WC-TiC層狀復(fù)合陶瓷刀具材料的設(shè)計原則,并根據(jù)這一設(shè)計原則分別選擇納米WC和TiC作為基體相與添加相;確定了粘結(jié)劑的成分為Ni,并對其潤濕性做了分析;對材料間化學(xué)相容性以及物理相容性進行了分析,證明了本課題選擇的材料符合層狀復(fù)合陶瓷刀具的設(shè)計原則。實驗研究了TiC含量、燒結(jié)溫度和保溫時間對碳纖維編織物增韌補強WC-Ti C層狀復(fù)合陶瓷刀具材料微觀組織和力學(xué)性能的影響。當燒結(jié)溫度為1500℃、燒結(jié)壓力為20MPa、TiC含量為10wt.%時,保溫30min的CWT11號陶瓷刀具的抗彎強度最高,達到905.30MPa,同樣的燒結(jié)溫度和TiC含量下,保溫45min的陶瓷刀具CWT31的維氏硬度和斷裂韌度最高,分別達到了20.21GPa和12.55MPa·m1/2。實驗分析了燒結(jié)溫度、TiC的質(zhì)量分數(shù)和燒結(jié)過程中的保溫時間對碳纖維編織物增韌補強WC-TiC層狀陶瓷刀具微觀組織的影響及刀具本身的增韌補強機理。結(jié)果表明,隨著TiC含量、燒結(jié)溫度和保溫時間的升高,材料的晶粒尺寸與氣孔率不斷增大,從而影響了材料的力學(xué)性能。分析材料的微觀組織可知,材料的主要增韌方式有裂紋的偏轉(zhuǎn)、橋聯(lián)、分叉以及纖維增韌、層狀復(fù)合增韌等。刀具同時存在沿晶斷裂與穿晶斷裂兩種斷裂方式。最后,實驗研究了刀具樣品與316 L奧氏體不銹鋼、GCr15軸承鋼、TC4鈦合金間的干摩擦磨損性能。通過對不同滑動速度與載荷下的材料間摩擦因數(shù)與磨損率的測試,研究了不同燒結(jié)溫度、TiC含量、保溫時間對刀具樣品摩擦因數(shù)和磨損率的影響,同時得到了不同滑動速度與載荷對材料摩擦因數(shù)和磨損率的影響。
[Abstract]:High speed cutting technology plays a very important role in the field of machining because of its high efficiency and precision. High speed cutting technology requires high performance of cutting tools. The tools used in high speed cutting are carbide tools, cermet tools, diamond tools, ceramic tools and so on. Ceramic cutting tools have attracted wide attention because of their superior performance and low price. However, the low toughness of ceramic cutters has seriously restricted their further promotion and application. In this paper, carbon was designed and prepared in accordance with its shortcomings. The toughening and reinforcing WC-TiC laminated ceramic tool material with fiber braided material was studied. The content of TiC was studied. The effects of sintering temperature and holding time on the mechanical properties and microstructure of WC-Ti C laminated ceramic cutters reinforced by carbon fiber braids; The toughening and reinforcing mechanism is analyzed. The friction and wear properties of ceramic tools and refractory materials were studied. The design principle of WC-TiC laminated ceramic tool materials toughened by carbon fiber braided material was put forward in this paper. According to this design principle, nano-WC and TiC were chosen as matrix phase and additive phase respectively. The composition of the binder was determined as Ni.The wettability of the binder was analyzed. The chemical compatibility and physical compatibility of the materials were analyzed. It was proved that the materials selected in this paper accord with the design principle of laminated ceramic tools. The content of TiC was studied experimentally. Effects of sintering temperature and holding time on microstructure and mechanical properties of WC-Ti C laminated ceramic tool materials toughened and reinforced by carbon fiber braided, when sintering temperature is 1500 鈩，

本文編號：1461547