文章信息/Info

Title:

The Influence of the Rolling Temperature on Through-Thickness Microstructures and Properties of TC4ELI Wide-Thick Plates

文章編號:

1674-3962(2025)06-0516-07

作者:

王立亞; 楊柳; 鄭友平; 康琴; 吳靜怡; 鐘勇

1. 成都先進金屬材料產業技術研究院股份有限公司，四川 成都 610399 2. 釩鈦資源綜合利用國家重點實驗室，四川 攀枝花 617099

Author(s):

WANG Liya;  YANG Liu ;  ZHENG Youping;  KANG Qin ;  WU Jingyi;  ZHONG Yong

1.Chengdu Advanced Metal Materials Industrial Technology Research Institute Co.,Chengdu 610399,China 2.State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization, Panzhihua 617099,China

關鍵詞:

TC4ELI合金; 寬厚板; 軋制溫度; 顯微組織; 力學性能; 厚度方向

Keywords:

TC4ELI alloy;  wide-thick plates;  rolling temperature;  microstructure; mechanical properties;  through-thickness

分類號:

TG146.23；TG335

DOI:

10.7502/j.issn.1674-3962.202501009

文獻標志碼:

A

摘要:

分別采用1050和900 ℃兩種軋制溫度制備出厚度為40 mm、寬度為~3700 mm的艦船用TC4ELI鈦合金寬厚板，通過室溫拉伸試驗、夏比沖擊試驗、金相分析、電子背散射衍射分析等研究了軋制溫度對該鈦合金寬厚板沿厚度方向微觀組織與力學性能分布特征的影響規律。結果表明，1050 ℃軋制的TC4ELI板材不同厚度層顯微組織和力學性能差異較大，表層為由等軸α相+片層α相+殘余β相組成的片層組織，強度和塑性高，沖擊功較低；1/4厚度和1/2厚度區域為由片層α相+殘余β相組成的片層組織，強度和塑性低，沖擊功較高。900 ℃軋制的TC4ELI板材不同厚度層顯微組織差別較小，均為雙態組織，表層區域初生α和次生α相的晶粒尺寸較小、心部區域晶粒尺寸較大。由于TC4ELI鈦合金板材的強化機制以細晶強化為主導，與1050 ℃軋制的板材相比，900 ℃軋制的板材強度和塑性均較高，而沖擊功較低。總之，兩相區軋制比單相區軋制更有助于微觀組織結構優化，可有效提升板材沿厚度方向微觀組織和力學性能的均勻性。

Abstract:

TC4ELI titanium alloy plates using for warships were rolled at 1050 and 900 ℃, respectively. The plates had a thicknesses of 40 mm and a width of about 3700 mm. The influence of rolling temperatures on the distribution characteristics of the microstructures and mechanical properties along the normal direction has been researched. Room temperature tensile tests, Charpy impact tests,metallographic analysis and electron backscatter diffraction analysis has been conducted. When rolled at 1050 ℃, there were significant differences in the microstructures and mechanical properties among different thickness areas. The surface areas had lamellar structures consisting of equiaxed α，lamellar α and residual β phases, with higher strength and plasticity but relatively lower impact toughness. The 1/4 thickness and 1/2 thickness areas had lamellar microstructure consisting of lamellar α and residual β phases and conversely had lower tensile strength and plasticity but higher impact toughness. When rolled at 900 ℃, the microstructures of different thickness layers had relatively smaller differences, with bimodal microstructures. The microstructures at surface areas had smaller grain sizes in both primary α phase and secondary α phase, while the microstructures at the central areas had larger grain sizes. Compared with the plates rolled at 1050 ℃, the plates rolled at 900 ℃ had higher tensile strength and plasticity but lower impact toughness, presenting evidence that fine-grain strengthening is the dominant mechanism for TC4ELI titanium alloy plates. In summary, rolling in the α/β phase region is more conducive to improving the microstructures and more effective to improve the uniformity of the microstructures and mechanical properties on through�瞭hickness of TC4ELI alloy plates, compared with rolling in the single β phase region.