机械工程学报
機械工程學報
궤계공정학보
CHINESE JOURNAL OF MECHANICAL ENGINEERING
2014年
21期
118-123
,共6页
史玉升%刘凯%李晨辉%魏青松%刘洁%夏思婕
史玉升%劉凱%李晨輝%魏青鬆%劉潔%夏思婕
사옥승%류개%리신휘%위청송%류길%하사첩
溶剂沉淀法%选泽性激光烧结%冷等静压%氧化锆
溶劑沉澱法%選澤性激光燒結%冷等靜壓%氧化鋯
용제침정법%선택성격광소결%랭등정압%양화고
solvent precipitation method%selective laser sintering%cold isostatic pressing%zirconia
氧化锆陶瓷材料以其优异的性能在工业生产中具有极大的应用前景,但由于脆性大、硬度高等原因,复杂形状氧化锆零件往往难以成形和加工。为了获得复杂形状氧化锆陶瓷零件,通过溶剂沉淀法将粘接剂尼龙12覆膜至纳米氧化锆粉末的表面,然后对覆膜后的粉体进行激光选区烧结(Selective laser sintering, SLS)成形,并通过传统的冷等静压(Cold isostatic pressing, CIP)技术对SLS零件进行致密化处理,同时满足氧化锆初坯成形时形状复杂度和密度的要求。通过试验得出在激光能量密度为0.415 J/mm2时,获得的SLS陶瓷件密度较大,对不同激光能量密度制备的SLS陶瓷件进行保压压力为200 MPa的冷等静压致密化处理,根据热脱脂机理以及粘接剂的TG曲线,分别制定了SLS/CIP试样的热脱脂工艺,最后对脱脂试样进行高温烧结,在后续处理的各环节,氧化锆零件的密度仍受SLS成形的影响,但该影响逐渐减弱,SLS/CIP/FS成形件最大相对密度和维氏硬度分别达到了97%和1180 HV1,已接近“模压-烧结”的致密氧化锆陶瓷的性能,在试样断口的扫描电子显微镜(SEM)分析基础上,对氧化锆复合成形的微观演变进行了研究。虽然最终烧结件密度和硬度仍有待提高,但是提出了一种极具潜力的氧化锆零件近净成形工艺方法,为制造高性能复杂形状的陶瓷零件奠定了基础。
氧化鋯陶瓷材料以其優異的性能在工業生產中具有極大的應用前景,但由于脆性大、硬度高等原因,複雜形狀氧化鋯零件往往難以成形和加工。為瞭穫得複雜形狀氧化鋯陶瓷零件,通過溶劑沉澱法將粘接劑尼龍12覆膜至納米氧化鋯粉末的錶麵,然後對覆膜後的粉體進行激光選區燒結(Selective laser sintering, SLS)成形,併通過傳統的冷等靜壓(Cold isostatic pressing, CIP)技術對SLS零件進行緻密化處理,同時滿足氧化鋯初坯成形時形狀複雜度和密度的要求。通過試驗得齣在激光能量密度為0.415 J/mm2時,穫得的SLS陶瓷件密度較大,對不同激光能量密度製備的SLS陶瓷件進行保壓壓力為200 MPa的冷等靜壓緻密化處理,根據熱脫脂機理以及粘接劑的TG麯線,分彆製定瞭SLS/CIP試樣的熱脫脂工藝,最後對脫脂試樣進行高溫燒結,在後續處理的各環節,氧化鋯零件的密度仍受SLS成形的影響,但該影響逐漸減弱,SLS/CIP/FS成形件最大相對密度和維氏硬度分彆達到瞭97%和1180 HV1,已接近“模壓-燒結”的緻密氧化鋯陶瓷的性能,在試樣斷口的掃描電子顯微鏡(SEM)分析基礎上,對氧化鋯複閤成形的微觀縯變進行瞭研究。雖然最終燒結件密度和硬度仍有待提高,但是提齣瞭一種極具潛力的氧化鋯零件近淨成形工藝方法,為製造高性能複雜形狀的陶瓷零件奠定瞭基礎。
양화고도자재료이기우이적성능재공업생산중구유겁대적응용전경,단유우취성대、경도고등원인,복잡형상양화고령건왕왕난이성형화가공。위료획득복잡형상양화고도자령건,통과용제침정법장점접제니룡12복막지납미양화고분말적표면,연후대복막후적분체진행격광선구소결(Selective laser sintering, SLS)성형,병통과전통적랭등정압(Cold isostatic pressing, CIP)기술대SLS령건진행치밀화처리,동시만족양화고초배성형시형상복잡도화밀도적요구。통과시험득출재격광능량밀도위0.415 J/mm2시,획득적SLS도자건밀도교대,대불동격광능량밀도제비적SLS도자건진행보압압력위200 MPa적랭등정압치밀화처리,근거열탈지궤리이급점접제적TG곡선,분별제정료SLS/CIP시양적열탈지공예,최후대탈지시양진행고온소결,재후속처리적각배절,양화고령건적밀도잉수SLS성형적영향,단해영향축점감약,SLS/CIP/FS성형건최대상대밀도화유씨경도분별체도료97%화1180 HV1,이접근“모압-소결”적치밀양화고도자적성능,재시양단구적소묘전자현미경(SEM)분석기출상,대양화고복합성형적미관연변진행료연구。수연최종소결건밀도화경도잉유대제고,단시제출료일충겁구잠력적양화고령건근정성형공예방법,위제조고성능복잡형상적도자령건전정료기출。
Zirconia has great application prospect for its excellent properties in the industrial production. But due to high brittleness and hardness, complex shape zirconia parts are often difficult to form and machine. To obtain complex zirconia parts, nano-zirconia powder is coated by the binder nylon 12 by solvent precipitation method. Coated powder is then formed via selective laser sintering (SLS) combined with cold isostatic pressing (CIP). Through the experiment, when laser energy density is 0.415 J/mm2, SLS ceramics had the biggest density. The subsequent 200 MPa CIP process is carried out on SLS parts with different laser energy density. According to the thermal debinding mechanism and TG curve of the binder, the reasonable thermal debinding process is formulated respectively. After furnace sintering (FS), with the steps of subsequent processing increased, parts affected by the SLS forming process gradually weakened, the largest relative density and Vickers hardness of SLS/CIP/FS parts are respectively 97%and 1180 HV1, radial and axial shrinkage rate were 58.1% and 67.8% respectively, and fracture of specimens are analysed by scanning electron microscope (SEM). Although the final density and hardness of the ZrO2 are still to be improved, a potential technical method for manufacturing complex zirconia parts with high performance is provided.