- 期刊
高錳合金化球墨鑄鐵之沃斯回火製程及機械行為研究
Study on Austempering Processes and Mechanical Behaviors of High Manganese Alloyed Ductile Iron
摘要
如眾所周知，球墨鑄鐵(Nodular graphite cast iron)經沃斯回火(Austempering)處理可獲得ADI之沃斯肥粒鐵組織以及優異的機械性質（強度、韌性、耐疲勞性等）。為了增加ADI的硬化能，如何有效地利用各種合金元素的添加來提高ADI產品的穩定性，則成為重要的研究課題。本研究目的主要是利用高錳含量(1wt%)的添加以增加ADI之硬化能，並進一步探討其對ADI機械性質（硬度、強度、韌性等）之影響，以尋求最佳的沃斯回火製程參數。 實驗結果顯示：添加1wt% Mn的鑄態球墨鑄鐵可增加硬度(149→166 HB)及抗拉強度(488→712 MPa)；對於ADI而言，在300℃-3h的「下沃斯回火」處理條件下，1wt% Mn-ADI比未添加ADI有較高的硬度(426 vs. 404 HB)及抗拉強度(1428 vs.1299 MPa)，而360℃-2h的「上沃斯回火」處理條件下，1wt% Mn-ADI比未添加ADI有較高的硬度(345 vs. 319 HB)及抗拉強度(1088 vs. 910 MPa)。
並列摘要
It is well known that austempered ductile iron (ADI) is made from nodular graphite cast iron by austempering treatment. ADI has excellent mechanical properties (high hardness, toughness, and fatigue strength) due to its ausferrite microstructure. In order to increase the hardenability of ADI, it is important to improve the stabilization of ADI via the addition of alloying elements. The purpose of this study is to add 1 wt% high Mn for raising the hardenability of ADI, and further explore the mechanical properties (hardness, strength, and toughness) of ADI for obtaining the optimal austempering condition. The results showed that 1 wt% Mn alloyed ductile iron increases the hardness (149→166 HB) and tensile strength (488→712 MPa) as compared with 0.25wt% Mn as-cast. For ADI treated with lower austempering (300℃-3h) treatment, 1 wt% Mn-ADI has higher hardness (426 vs. 404 HB) and tensile strength (1428 vs.1299 MPa) than that of 0.25 wt% Mn-ADI, while for ADI treated with austempering (360℃-2h) treatment, 1 wt% Mn-ADI has higher hardness (345 vs. 319 HB) and tensile strength (1088 vs. 910 MPa) than that of 0.25 wt% Mn-ADI.