發(fā)布時(shí)間：2018-03-15 20:35

  本文選題：ADI　切入點(diǎn)：工藝　出處：《哈爾濱理工大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：等溫淬火球墨鑄鐵(ADI),是公認(rèn)的綜合力學(xué)性能優(yōu)良的材料。由于其組織是由針狀鐵素體、殘余奧氏體和石墨球組成,使其又有良好的減振降噪性,可作為設(shè)備的傳動(dòng)部件。以往人們只注重ADI力學(xué)性能方面的研究,而對(duì)其阻尼性能的研究罕見報(bào)道,因此,本文系統(tǒng)的研究和分析了爐前處理及熱處理工藝對(duì)ADI阻尼性能的影響規(guī)律,為研發(fā)高阻尼ADI奠定基礎(chǔ)。本文采用動(dòng)態(tài)機(jī)械分析儀(DMA)對(duì)不同爐前處理及熱處理工藝下ADI試樣的阻尼性能進(jìn)行測試,利用金相顯微鏡及X射線衍射儀(XRD)對(duì)組織進(jìn)行分析。不同爐前處理工藝下試樣的應(yīng)變-內(nèi)耗曲線顯示:在應(yīng)變?yōu)?.05%時(shí),一次孕育劑加入量為1.0~1.4%時(shí)阻尼性能較優(yōu)異,內(nèi)耗值Q-1可達(dá)0.02以上;二次孕育劑加入量為0.2%時(shí)阻尼性能最佳,內(nèi)耗值Q-1達(dá)到了0.025左右;球化劑加入量為1.1~1.5%時(shí)阻尼性能較優(yōu),內(nèi)耗值Q-1超過了0.018;結(jié)合組織分析可知:石墨球形狀、尺寸及球化率差別不大的情況下,ADI組織中石墨球的數(shù)量越多,則越有益于提升ADI的阻尼性能。不同熱處理工藝下試樣的應(yīng)變-內(nèi)耗曲線顯示:在應(yīng)變?yōu)?.05%時(shí),奧氏體化溫度為900℃時(shí)阻尼性能最佳,內(nèi)耗值Q-1達(dá)到了0.017左右;第一步等溫淬火溫度為240~260℃時(shí)阻尼性能較優(yōu),內(nèi)耗值Q-1超過了0.014;第二步等溫淬火溫度為320℃時(shí)阻尼性能最佳,內(nèi)耗值Q-1超過了0.017;第一步等溫淬火時(shí)間為10~15 min時(shí)阻尼性能優(yōu)異,內(nèi)耗值Q-1超過了0.016;第二步等溫淬火時(shí)間為40~60 min時(shí)阻尼性能較優(yōu),內(nèi)耗值Q-1可達(dá)0.017以上,完全符合高阻尼合金的標(biāo)準(zhǔn)(Q-10.01);結(jié)合組織分析可知:ADI基體中形核數(shù)量越多、晶粒尺寸越小,則越有益于提升其阻尼性能,同時(shí),基體中殘余奧氏體含量對(duì)其阻尼性能也有一定的影響。本文研究發(fā)現(xiàn),ADI的阻尼性能對(duì)測試溫度和頻率較敏感,試驗(yàn)結(jié)果表明:隨著測試溫度的升高,ADI的阻尼性能逐步上升,在180~220℃時(shí)達(dá)到峰值Q-1為0.029左右,繼續(xù)升溫則阻尼性能逐漸降低;測試頻率范圍為1~100 Hz時(shí),隨著測試頻率的提升,ADI的阻尼性能有上升的趨勢。
[Abstract]:Isothermal quenched ductile iron is recognized as a material with excellent comprehensive mechanical properties. Its structure is composed of acicular ferrite, residual austenite and graphite ball, which makes it have good vibration and noise reduction. In the past, people only paid attention to the study of mechanical properties of ADI, but rarely reported its damping property. In this paper, the influence of furnace pretreatment and heat treatment on the damping properties of ADI is systematically studied and analyzed. In this paper, a dynamic mechanical analyzer is used to test the damping properties of ADI samples under different furnace pretreatment and heat treatment processes. The microstructure was analyzed by metallographic microscope and X-ray diffractometer (XRD). The strain-internal friction curves of different furnace pretreatment processes showed that when the strain was 0.05 and the amount of inoculant was 1.0 ~ 1.4, the damping property of the sample was better. The internal friction value Q-1 can be more than 0.02, the damping property is the best when the secondary inoculant dosage is 0.2, the internal friction value Q-1 is about 0.025, and the damping property is better when the nodularizing agent dosage is 1.1 ~ 1.5. The internal friction value Q-1 was more than 0.018.The results of microstructure analysis showed that the number of graphite spheroids in ADI was more when the shape, size and spheroidization rate of graphite spheroidization were not different. The strain-internal friction curves of the samples under different heat treatment conditions show that when the strain is 0.05 鈩，

本文編號(hào)：1616704