本文選題：增材制造 + 無模鑄型制造技術(shù)�。� 參考：《太原理工大學(xué)》2017年碩士論文

【摘要】：無模鑄型制造技術(shù)(Patternless Casting Manufacturing,簡稱PCM技術(shù))是將數(shù)字化信息驅(qū)動制造技術(shù)與樹脂砂鑄造技術(shù)巧妙結(jié)合的新型增材制造技術(shù)。其具有生產(chǎn)效率高、成本低、適合個性化定制等諸多優(yōu)勢,在制造業(yè)領(lǐng)域有著廣闊的應(yīng)用前景。就無模鑄型制造技術(shù)而言,造型材料選擇至關(guān)重要,呋喃樹脂以其粘度低、滲透性好、強度高、舊砂回用性好等優(yōu)點,在國內(nèi)無模鑄型制造技術(shù)中得到了普遍應(yīng)用。但是,呋喃樹脂的酸耗值較高,對原砂要求較高,高溫穩(wěn)定性較差,發(fā)氣量較高,而且由于游離醛、游離酚的大量存在,增大了有害氣體揮發(fā)量,在一定程度上影響了鑄件質(zhì)量。堿性酚醛樹脂無酸耗性要求,對原砂適應(yīng)性好、高溫穩(wěn)定性好、發(fā)氣量相對較低。本文針對當(dāng)前呋喃樹脂存在的問題,進(jìn)行了堿性酚醛樹脂在無模鑄造技術(shù)中的應(yīng)用可行性研究,并進(jìn)行了實驗驗證。針對無模鑄型制造技術(shù)的特點與要求,選取了兩種不同固化機理的堿性酚醛樹脂,分別為酯固化自硬堿性酚醛樹脂和熱固型堿性酚醛樹脂。研究了酯固化自硬堿性酚醛樹脂和熱固型堿性酚醛樹脂的固化機理,分別對其適用性進(jìn)行探究。酯固化自硬堿性酚醛樹脂粘度高達(dá)80mPa?s,無法適配到當(dāng)前設(shè)備的噴嘴中,選定無水乙醇作為稀釋劑,在優(yōu)化稀釋比例為50%的條件下,引入十二烷基苯磺酸鈉作為表面活性劑,使其粘度降到適用范圍。在驗證手工造型強度的基礎(chǔ)上,進(jìn)行PCM工藝驗證。發(fā)現(xiàn)鑄型抗拉強度僅為0.2 MPa,難以滿足實際鑄造的要求。目前看來,酯固化堿性酚醛樹脂在PCM工藝中還達(dá)不到適用的條件。熱固型堿性酚醛樹脂通過30%無水乙醇稀釋,粘度降至13.0 m Pa?s,同時滿足了PCM技術(shù)的噴射工藝要求。通過實驗確定了后處理工藝,實驗表明180℃固化溫度下固化60min的鑄型滿足澆鑄要求。后期,對熱固型堿性酚醛樹脂進(jìn)行PCM工藝上機實驗,得到的鑄型強度達(dá)到0.8MPa,發(fā)氣量達(dá)到15.6ml/g。滿足實際鑄造要求。本文通過以上幾個方面的論證和實驗,得到了強度和發(fā)氣性都滿足實際鑄造要求的鑄型。將采用熱固型堿性酚醛樹脂在PCM工藝下打印出的階梯試塊進(jìn)行澆鑄,成功得到表面質(zhì)量良好的階梯試塊鑄件。經(jīng)過拉伸實驗,確定該鑄件滿足強度標(biāo)準(zhǔn)。至此,成功地將一種堿性酚醛樹脂應(yīng)用到無模鑄型制造技術(shù)中,拓寬了無模鑄型制造技術(shù)的使用范圍,也為無模鑄型制造技術(shù)的下一步技術(shù)優(yōu)化提供了一定的參考。
[Abstract]:Patternless casting Manufacturing (PCM) is a new material increasing manufacturing technology which combines digital information driven manufacturing technology with resin sand casting technology. It has many advantages, such as high production efficiency, low cost, suitable for individualized customization, and has a broad application prospect in the field of manufacturing. As far as the mouldless manufacturing technology is concerned, the selection of moulding material is very important. Furan resin has been widely used in the mouldless moulding manufacturing technology in China because of its advantages of low viscosity, good permeability, high strength and good reusability of used sand. However, the acid consumption of furan resin is high, the demand of raw sand is higher, the stability of high temperature is poor, the amount of gas is high, and the volatile amount of harmful gas is increased because of the existence of free aldehyde and free phenol. The casting quality is affected to some extent. Basic phenolic resin has no demand for acid consumption, good adaptability to raw sand, good high temperature stability and relatively low gas generation. In view of the existing problems of furan resin, the feasibility of the application of basic phenolic resin in die less casting technology was studied, and the experiment was carried out. In view of the characteristics and requirements of the mouldless manufacturing technology, two kinds of alkalic phenolic resins with different curing mechanisms were selected, namely, ester cured self-hardening basic phenolic resins and thermosetting basic phenolic resins. The curing mechanism of ester cured self-hard basic phenolic resin and thermosetting basic phenolic resin was studied. The viscosity of ester solidified from hard basic phenolic resin is up to 80 mPas, which can not be adapted to the nozzle of current equipment. Anhydrous ethanol is selected as diluent and sodium dodecyl benzene sulfonate is introduced as surfactant under the optimized dilution ratio of 50%. Reduce its viscosity to the applicable range. On the basis of verification of manual molding strength, PCM process verification is carried out. It is found that the tensile strength of mold is only 0.2 MPA, which is difficult to meet the requirement of actual casting. At present, the ester-cured basic phenolic resin in the PCM process can not meet the applicable conditions. The viscosity of thermosetting basic phenolic resin was reduced to 13.0 m Paans by 30% anhydrous ethanol dilution, which met the requirements of PCM spray technology at the same time. The post-treatment process was determined by experiments. The results showed that the casting mold of solidified 60min at 180 鈩，

本文編號：2013168