本文選題：多孔鈦 + 鈦-鎂復(fù)合材料�。� 參考：《哈爾濱工業(yè)大學(xué)》2017年碩士論文

【摘要】：鈦及鈦合金以其高的比強(qiáng)度、良好的耐蝕性和生物相容性等優(yōu)點(diǎn)已成為目前具有發(fā)展?jié)摿Φ囊环N生物醫(yī)用材料,但是鈦及鈦合金存在著的最大的兩個(gè)不足便是:彈性模量過高(TC4合金彈性模量為110GPa),會(huì)產(chǎn)生“應(yīng)力屏蔽”效應(yīng);鈦屬于生物惰性材料,但是不能誘導(dǎo)促進(jìn)骨組織的生長。鎂合金以其較低的彈性模量、良好的骨整合性和骨誘導(dǎo)性以及可降解性等優(yōu)點(diǎn)也成為發(fā)展前景廣闊的一種生物醫(yī)用材料,但是鎂合金耐腐蝕性較差、強(qiáng)度較低成為了限制其發(fā)展的最大瓶頸。本論文以開發(fā)一種低彈性模量、強(qiáng)度高、在人體內(nèi)可以起到承載作用并具有較好的生物相容性且新型生物醫(yī)用材料為目的。利用低彈性模量的多孔鈦和具有良好的骨整合性與骨誘導(dǎo)性的鎂,將鎂通過超聲波輔助浸滲的方法滲入多孔鈦的孔隙中制備出了鈦-鎂復(fù)合材料。為了在原材料選用和加工制備過程中不引入有害元素,因此選用高純球形鈦粉利用燒結(jié)的方法來制備多孔鈦。通過不同工藝參數(shù)的燒結(jié)實(shí)驗(yàn)研究了鈦粉尺寸、燒結(jié)壓力、燒結(jié)溫度、燒結(jié)時(shí)間和燒結(jié)路徑對(duì)多孔鈦形貌和性能的影響規(guī)律,優(yōu)化出多孔鈦的燒結(jié)工藝為:900℃保溫50min后進(jìn)行簡單清潔加工,然后進(jìn)行1200℃燒結(jié)120min,獲得孔隙質(zhì)量好、表面清潔、強(qiáng)度高的多孔鈦。采用超聲波輔助浸滲的方式,利用超聲波的“空化”作用提高鈦和鎂之間的潤濕性,獲得了結(jié)構(gòu)致密的鈦-鎂復(fù)合材料。通過掃描電子顯微鏡(SEM)、X射線衍射(XRD)的表征發(fā)現(xiàn)鈦和鎂在室溫下基本不互溶且不存在第二相。鈦和鎂的界面結(jié)合致密,存在擴(kuò)散層,提高了界面結(jié)合強(qiáng)度。雙連續(xù)鈦-鎂復(fù)合材料繼承了作為骨架的多孔鈦的力學(xué)性能特征。鎂的加入起到了對(duì)材料的穩(wěn)定和強(qiáng)化作用。鈦顆粒粒徑分別是230μm、130μm和100μm的復(fù)合材料的彈性模量為23.4GPa、33.6GPa和37.6GPa,壓縮屈服強(qiáng)度分別為230.2MPa、262.9MPa和300.1MPa,抗彎強(qiáng)度為375.2MPa、468.8MPa、631.5MPa。彈性模量在人骨的彈性模量水平,可避免“應(yīng)力屏蔽”效應(yīng),壓縮屈服強(qiáng)度和抗彎強(qiáng)度均高于人骨的強(qiáng)度,因此可以滿足在人體內(nèi)的承載服役要求。由于鈦鎂的復(fù)合,材料內(nèi)形成了原電池,因此材料的耐腐蝕性被降低。鎂被選擇性腐蝕留下孔隙,可以為骨組織生長和營養(yǎng)物質(zhì)的運(yùn)輸提供空間,且腐蝕產(chǎn)物鎂離子為人體的常量元素。因此鈦-鎂復(fù)合材料具有良好的生物相容性,但是耐腐蝕性有待進(jìn)一步研究來提高,首先商業(yè)純鎂的耐蝕性差,其次鈦和鎂的直接復(fù)合形成電偶腐蝕加速鎂的腐蝕。利用直接氧化的方法在鈦和鎂的界面上形成一層氧化層,但由于其連續(xù)性較差而且不能完全阻止鈦和鎂之間的擴(kuò)散,對(duì)材料的耐蝕性沒有明顯的改善,復(fù)合材料的力學(xué)性能由于鈦氧化層的引入而有所降低但仍然滿足性能要求,因此證明了只要選用合適的擴(kuò)散障層,該方法是可行的。
[Abstract]:Titanium and titanium alloys have become a kind of biomedical materials with high specific strength, good corrosion resistance and biocompatibility. However, titanium and titanium alloy have two biggest shortcomings: the high elastic modulus of TC4 alloy is 110 GPA, which will produce "stress shielding" effect, and titanium is a biological inert material, but it can not induce the growth of bone tissue. Magnesium alloys have become a promising biomedical material for their low modulus of elasticity, good bone integration, bone induction and degradability, but magnesium alloys have poor corrosion resistance. Low intensity has become the biggest bottleneck limiting its development. The purpose of this paper is to develop a new biomedical material with low elastic modulus, high strength, good biocompatibility and bearing capacity in human body. Using porous titanium with low modulus of elasticity and magnesium with good bone integration and bone induction, titanium magnesium composites were prepared by infiltration of magnesium into the pores of porous titanium by ultrasonic infiltration. In order to avoid the introduction of harmful elements in the selection and preparation of raw materials, high purity spherical titanium powder was used to prepare porous titanium by sintering. The effects of titanium powder size, sintering pressure, sintering temperature, sintering time and sintering path on the morphology and properties of porous titanium were studied by sintering experiments with different technological parameters. The sintering process of porous titanium was optimized as follows: 1: 900 鈩，

本文編號(hào)：1774374