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注浆成型陶瓷模具石膏改性研究重庆大学硕士学位论文（专业学位）学生姓名：朱登玲指导教师：彭家惠教授学位类别：工程硕士（材料科学与工程领域）重庆大学材料科学与工程学院二O一四年四月StudyontheModificationofSlipCastingCeramicsMouldGypsumAThesisSubmittedtoChongqingUniversityinPartialFulfillmentoftheRequirementforProfessionalDegreeByZhuDenglingSupervisedbyProf.PengJiahuiSpecialty:ME(MaterialEngineeringField)CollegeofMaterialScienceandEngineeringofChongqingUniversity,Chongqing,ChinaApril,2014重庆大学硕士学位论文中文摘要I摘要由于石膏模具有原材料来源广泛、成本低廉、吸水性能好、尺寸稳定、复制清晰、棱角线条突出不易污染环境等优点，一直被卫生陶瓷行业广泛应用。但疏松多孔石膏模具有自身的一些缺点如强度低，耐溶蚀性、耐磨性及耐水性差，一般仅使用60～90次，远低于国际平均水平。因此，改善石膏模的性能具有非常重要经济价值与研究意义。成型是石膏模使用的基础。成型工艺则是影响模具性能的关键因素。本文系统研究了成型工艺（水膏比、搅拌时间、水温）对陶瓷模具石膏性能的影响。最终确定最佳成型工艺组合为：水膏比为1:1.6、搅拌时间为2min、水温20℃。从提高石膏模性能角度出发，研究了聚羧酸减水剂、聚丙烯纤维、玻璃纤维、石英砂、硅酸盐水泥、高铝水泥及硫铝酸盐水泥对模具石膏宏观性能的影响，并采用SEM、DSC-TG、XRD及MIP等微观分析手段深入分析探索其作用机理。结果表明：相同流动度条件下，聚羧酸系减水剂减少拌合水用量，使复合硬化体孔隙率降低、孔径细化从而显著提高其强度及耐溶蚀性，其最佳掺量为0.15%。模具石膏中掺入适量纤维可增加石膏基体连续性，有效抑制硬化体裂缝的发展缓和裂缝尖端应力集中程度，显著提高模具石膏抗折强度；但掺量过大，纤维会产生弯曲成团现象形成应力集中进而降低石膏模的强度；由于玻璃纤维性脆、耐磨性差且PPF增强作用优于GF，因此最佳纤维类型为聚丙烯纤维，其最佳掺量为0.04wt%。石英砂本身硬度很高及小粒径石英砂对石膏硬化体孔隙的填充作用是石英砂显著提高硬化体抗折强度及耐磨性的主要原因，其最佳掺量为10%。对比研究硅酸盐水泥、高铝水泥及硫铝酸盐水泥对模具石膏抗折强度、耐水性及耐溶蚀性的影响，结果表明，最佳水泥类型为硫铝酸盐水泥，最佳掺量为8%；此时硫铝酸盐水泥与石膏共同水化生成的针棒状DH与细针状AFt相互搭接交织生长形成网状结构，AH3凝胶及C-S-H凝胶则紧密填充于网络结构晶隙间进一步增加硬化体稳定性及密实性，改变硬化体孔径结构使孔径细化，降低其孔隙率，显著提高模具石膏强度、耐水性及耐溶蚀性。综上所述，当水膏比为0.65、搅拌时间为2min、水温为20℃并掺入0.15%聚羧酸减水剂、0.04wt%聚丙烯纤维、10%石英砂、8%硫铝酸盐水泥能制备性能较好的石膏模。关键词：陶瓷模具石膏，成型工艺，外加剂，抗折强度，吸水率重庆大学硕士学位论文英文摘要IIABSTRACBecauseofthegypsum-model’sadvantageslikerichinrawmaterialoriginate,lowcost,goodwaterabsorbingperformance,dimensionstability,clearoutlineandhavingnopollutiontoenvironment,ithasbeenextensivelyappliedinsanitaryceramicindustry.However,gypsum-moldalsohasalotofdisadvantages,suchas:lowstrength,badcorrosion-resistance,badabrasion-resistanceandbadwater-resistance,whichshortentheuselifeofthegypsum-mold.InChina,theusetimesofgypsum-moldaresixtytoninetycommonly,whichisfarbelowtheinternationalaveragelevel.Therefore,improvingthecomprehensivepropertyofmouldgypsumhasaveryimportanteconomicvalueandresearchsignificance.Moldingisthebasisofgypsum-molduse.Moldingtechnologyisthekeyfactoraffectingtheall-roundperformanceofmould.Themacro-performancesandmicrostructureofgypsum-moldwerediscussedbychangingmoldingprocess(water-gypsumratio,stirringtimeandwatertemperature).Finally,theoptimalmoldingtechnologyis:W/G1:1.6,stirringtime2min,watertemperature20℃.Toimprovethecomprehensivepropertyofgypsum-mold,themacro-performancesandmicrostructureofgypsum-moldwereresearchedbytheadditionofwaterreducer,silicatesand,polypropylenefiber,glassfiber,Portlandcement,aluminatecementandsulphoaluminatecement）.ThemechanismswereanalyzedbymeasurementsofSEM,DSC-TG,XRDandMIP.Theresultindicatedthattoreachtheequalfluidity,mixingwaterofgypsum-moldwasreducedgreatlybycontentgrowingofwaterreducer.Theporosityandaverageporesizeofhardenedgypsumwerealsodecreased,whichenhancedthestrengthandcorrosion-resistanceremarkably.Theoptimumcontentofwaterreducerwas0.15%.Thecontinuityandtoughnessofgypsum-moldwasstrengthenedevidentlybytheadditionoffibermoderately.Thefibercanhinderthegrowthofcracksandalleviatethestressconcentrationatcracktip.Theflexuralstrengthofmodel-gypsumwasincreasedbythecontentoffiberconsequently.Whentheadditionofthefiberwastoolarge,thegypsumwouldproducebendingandstressconcentration.Theperformanceofgypsum-moldwasdecreasedbythecontentoffiber.GFwasbrittleandbadabrasion-resistance.ThereinforcedeffectofPPFwasbetterthanGF.Therefore,theoptimalfiberforgypsum-moldwasPPFandtheoptimumcontentwas0.04wt%.Themostimportantreasonstoenhancetheperformanceofflexuralstrength重庆大学硕士学位论文英文摘要IIIandabrasion-resistancearethehighhardnessofsilicatesandandthefillingforporeingypsumwithsmallsize.Theoptimumadditionofsilicatesandis10%.Theperformancesofflexuralstrength,water-resistanceandcorrosion-resistanceofmodel-gypsumwereenhancedsignificantlybytheadditionofPortlandcement,aluminatecementandsulphoaluminatecement.Comparisonofthreekindsofcementsonthecomprehensivepropertyofthegypsum-mold,thebestcementforgypsum-moldissulphoaluminatecementandtheoptimumadditionis8%.TheDHandAFtwhichareproducedbytheadditionofSACarelappedtoformadensenetworkstructure.TheporespacewasfilledwithC-S-HandAH3closelytomaketheporosityandaverageporesizeofthegypsumdecreased.Thestructurestabilityandcompactibilitywasstrengthenedgreatly,consequently.Themacro-performanceofstrength,water-resistanceandcorrosion-resistancewereimprovedobviously,too.Inaword,thecomprehensivepropertyofgypsum-moldwasstrengthenedobviouslyattheW/G0.65,stirringtime2min,watertemperature20℃,waterreducer0.15%，PPF0.04wt%，silicatesand10%andSAC8%.Keywords:Ceramicsmouldgypsum,Moldingtechnology,Admixture,Flexuralstrength,Waterabsorption重庆大学硕士学位论文目录IV目录中文摘要..........................................................................................................................................I英文摘要........................................................................................................................................II1绪论...................................................................