文章信息/Info

Title:

New High Strength and High Toughness Titanium Alloy with 1200 MPa

作者:

趙永慶; 馬朝利; 常 輝; 辛社偉; 周 廉

西北有色金屬研究院，北京航空航天大學(xué)，南京工業(yè)大學(xué)

Author(s):

ZHAO Yongqing;  MA Chaoli;  CHANG Hui;  XIN Shewei;  ZHOU Lian

Northwest Institute for Nonferrous Metal Research，Beihang University，Nanjing Tech University

關(guān)鍵詞:

高強(qiáng)韌鈦合金; 成分設(shè)計(jì); 組織; 力學(xué)性能

DOI:

10.7502/j.issn.1674-3962.2016.12.05

文獻(xiàn)標(biāo)志碼:

A

摘要:

隨著飛機(jī)結(jié)構(gòu)件用鈦量的大幅度增加，對(duì)鈦合金的性能要求也隨飛機(jī)設(shè)計(jì)概念的改變而改變，在追求鈦合金高強(qiáng)度的同時(shí)，也要求合金具有高的韌性。為設(shè)計(jì)一種強(qiáng)度高于1200 MPa、斷裂韌性大于65 MPa·m1/2的新型高強(qiáng)高韌鈦合金，在計(jì)算合金Mo當(dāng)量的基礎(chǔ)上，合金設(shè)計(jì)時(shí)綜合考慮了合金元素對(duì)α相、β相的強(qiáng)化和韌化的影響，以及微觀組織對(duì)強(qiáng)韌性的影響，設(shè)計(jì)獲得一種新型高強(qiáng)高韌富β型的鈦合金Ti-5321。實(shí)驗(yàn)室條件下30 kg鑄錠和中試條件下500 kg鑄錠試制的棒材在較理想的顯微組織下，新設(shè)計(jì)的合金室溫抗拉強(qiáng)度大于1200 MPa、延伸率大于8%、斷裂韌性大于65 MPa·m1/2，相比于現(xiàn)有高強(qiáng)高韌鈦合金，顯示出明顯優(yōu)勢(shì)。

Abstract:

Ti usage in airplane is obviously increasing, the requirements for Ti-alloys are changing to high strength and high toughness with the changing of airplane design concept. In order to design a new Ti-alloy with tensile strength over 1200 MPa and fracture toughness over 65 MPa·m1/2, the following factors should be paid attention to: Mo equivalent, effects of alloying elements and microstructures on strength and toughness of α phase and β phase. A new Ti alloy named as Ti5321 was designed, which is a rich-β alloy. Bars were forged from 30 kg and 500 kg ingots. With the ideal microstructure, the bars of the new alloy have a good match between strength and toughness, that is , tensile strength over 1200 MPa, elongation over 8% and fracture toughness over 65 MPa·m1/2. Compared with the TC21, Ti-5553 and Ti-55531 alloy, the new alloy possesses obvious advantages.