1、Influence of silicon and addition elements on the mechanical behavior of ferritic ductile cast ironn報告人：員飛n學(xué)號：157221001主要內(nèi)容：主要內(nèi)容：2o研究背景研究背景o實驗過程實驗過程o微觀組織與分析微觀組織與分析o結(jié)論結(jié)論1.研究背景優(yōu)點可切削加工性能好耐蝕性強抗氧化性高耐磨性強32.試驗過程拉伸試驗：測定拉伸強度，屈服強度，斷后伸長率。沖擊試驗：測定常溫沖擊韌性EBSD：測定鐵素體晶粒尺寸金相分析與掃描電鏡：微觀組織與斷面4Table1Chemical composition o

2、f ferritic ductile iron(wt%)5CSiNiCuMnPSCrMgSn2.793.800.020.040.070.0180.0110.0250.0500.0703.394.500.390.400.202.試驗過程 Minimum required values for mechanical properties of ferritic ductile iron6Ductile ironTensile strength (MPa)Yieldingstress (MPa)ElongationA%GJS 600-10580450870GJS 500-14 4804001280T

3、able22.試驗過程2.試驗過程硅添加量與拉伸強度和屈服強度的關(guān)系72.試驗過程硅添加量與斷后延長率和沖擊韌性的關(guān)系82.試驗過程Fig. 5. Influence of copper content on properties of ductile cast iron:(a)tensilestrength and yielding stress, (b)failure strain and resilienceab9Fig. 6. Influence of nickel content on properties of ductile cast iron:(a)tensile streng

4、th and yielding stress.and(b)failure strain and resilience 2.試驗過程10Fig. 7. Inverse pole figure of ductile cast iron.3.微觀分析113.微觀分析Fig. 8. Silicon segregation zones between two graphite nodules.123.微觀分析Fig. 9. Variation of chemical composition of GJS500-7,between two graphite nodules:(a)1st zone:439

5、mm long with a step of 18 mm, and(b)2nd zone:304 mm long with a step of 12 mm. 133.微觀分析Fig. 10. Micrograph of ductile iron(ferritic matrix with a few darken islands of pearlite).14Fig. 11. Failure surfaces of ductile cast iron(non-notched Charpy samples failed at ambient temperature):(a)brittle cleavage failure,and(b)ductilebrittle intergranular failure.3.微觀分析15Fig. 12. Matrix/nodules decohesion and crackes in ductile iron(images represent two analysis zones). 3.微觀分析164.結(jié)論1.在一定程度上提高硅的含量可以使材料的抗拉強度和屈服強度明顯升高，但同時材料斷后伸長率和沖擊韌性有所下降。2.按照力學(xué)性能的要求，硅的添加量需要控制在0.125-0.25%，超過或者低于此含量