摘要
目的探讨数字光处理(digital light processing,DLP)三维打印和数控切削(computer numerical controlmilling,CNC)两种加工工艺对氧化锆力学性能的影响。方法分别制备DLP和CNC试件各52个,采用随机数字表随机各选取12个试件,进行密度和晶粒尺寸测量以及晶相成分分析。再根据断裂韧性测试方法将试件分为维氏压痕法(indentation method,IM)组(DLP和CNC试件各30个)和单边V形切口梁法(single-edge-V-notch-beam,SEVNB)组(DLP和CNC试件各10个)。IM组试件在49.03、98.07、196.10 N载荷下进行实验,两种试件每种载荷各10个试件,每个试件测15个点,根据压痕选择最适宜的载荷并计算该载荷下的IM断裂韧性。SEVNB组进行四点弯曲测试,记录试件压断时的最大载荷,计算SEVNB断裂韧性。采用光学显微镜和扫描电镜观察DLP和CNC试件压痕和断面。结果DLP和CNC氧化锆微观结构基本一致,DLP氧化锆密度为(6.020±0.021)g/cm^(3),晶粒尺寸为(0.603±0.033)μm;CNC氧化锆密度为(6.038±0.012)g/cm^(3),晶粒尺寸为(0.591±0.033)μm;两种试件均由四方相氧化锆组成。两种氧化锆试件IM测试最适宜的载荷均为196.10 N。DLP氧化锆的IM和SEVNB断裂韧性值分别为(6.111±0.179)和(7.221±0.809)MPa·m^(1/2);CNC氧化锆的IM和SEVNB断裂韧性值分别为(6.126±0.383)和(7.408±0.533)MPa·m^(1/2);两种氧化锆的IM断裂韧性差异和SEVNB断裂韧性差异均无统计学意义(P>0.05)。断面扫描电镜图像均示以沿晶断裂为主的混合断裂模式。结论DLP氧化锆的微观结构与CNC氧化锆几乎相同,DLP和CNC加工工艺对氧化锆断裂韧性的影响差别不大。
Objective To investigate the influence of digital light processing(DLP)and computer numerical controlmilling(CNC)on the mechanical behavior of zirconia.Methods Prepared DLP samples(experimental group,n=52)and CNC samples(control group,n=52)with 12 samples in each group were randomly selected using random number table to measure density,grain size and crystal phase composition.According to the different methods fracture toughness test,the samples were divided into indentation method group(IM)and single-edge-V-notch-beam group(SEVNB),with 30 DLP and 30 CNC samples in IM group,10 DLP and 10 CNC samples in SEVNB group.The IM group was tested under three different loads(49.03 N,98.07 N,196.10 N),there were 10 samples for each load and each sample was tested at 15 points,and the load with the ratio of crack length to indentation diagonal length greater than 2.5 was selected as the indentation load to calculate its IM fracture toughness.At the same time,the SEVNB group was tested with four point bending test to record the maximum load at the time of fracture and calculate the SEVNB fracture toughness.Finally,the indentation and fracture surface were observed using optical microscope and scanning electron microscope,and the results of DLP group and CNC group were further compared to explore the difference in fracture mechanism.Results The microstructure of DLP and CNC zirconia was basically the same,the density of DLP group was(6.020±0.021)g/cm^(3),the grain size was(0.603±0.033)μm;the density of CNC group was(6.038±0.012)g/cm^(3),the grain size was(0.591±0.033)μm.Both groups were composed of tetragonal zirconia.The load of 196.10 N was chosen as the indentation load for two groups to calculate the IM fracture toughness.In terms of fracture toughness,there was no significant difference between the two groups(P>0.05).Scanning electron microscope images of fracture surface showed the intergranular fracture was the leading fracture mode of two groups.The IM and SEVNB fracture toughness of DLP zirconia were(6.111±0.179)MPa·m^(1/2) and(7.221±0.809)MPa·m^(1/2),respectively.The IM and SEVNB fracture toughness of CNC zirconia were(6.126±0.383)MPa·m^(1/2) and(7.408±0.533)MPa·m^(1/2),respectively.Conclusions The microstructure of DLP and CNC zirconia is almost the same,and there is little difference in the fracture toughness of zirconia between two processing technologies.
作者
楼雨欣
鲁雨晴
梅子彧
孙蔓琳
孙纪奎
于海洋
Lou Yuxin;Lu Yuqing;Mei Ziyu;Sun Manlin;Sun Jikui;Yu Haiyang(Department of ProsthodonticsⅡ,West China Hospital of Stomatology,Sichuan University&State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases,Chengdu 610041,China)
出处
《中华口腔医学杂志》
CAS
CSCD
北大核心
2021年第7期639-645,共7页
Chinese Journal of Stomatology
基金
四川省科技计划重点研发项目(2020YFS0040)。
关键词
牙瓷料
显微镜检查
电子
扫描
氧化锆
三维打印
数字光处理
断裂韧性
Dental porcelain
Microscopy,electron,scanning
Zirconia
Three-dimensional printing
Digital light processing
Fracture toughness
