文章信息/Info

Title:

Progress in ICME Approach to Design of Novel Microstructures for Ti-Alloys

作者:

王棟; 王云志

西安交通大學前沿科學技術研究院，金屬強度國家重點實驗室，陜西西安 710049

Author(s):

Dong Wang;  Yunzhi Wang

Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China

關鍵詞:

鈦合金; 相變; 偽調幅分解機理; 計算機模擬; 相場動力學

DOI:

10.7502/j.issn.1674-3962.2015.04.04

文獻標志碼:

A

摘要:

基于集成計算材料工程的思想，結合CAPHAD、相場動力學模擬與關鍵的實驗測量手段，以及鈦合金中最新發現的非傳統的固 - 固相變，近來提出的偽調幅分解相變機制為鈦合金微觀結構設計提出了新的方向。這一機制首先被Ni 和Khachaturyan提出并用來解釋斜紋組織的形成，并被Fraser等人引入到鈦合金體系，Banerjee和wang等人通過實驗和模擬證明其正確性，這種新的轉變途徑為設計具有超細、超均勻???相微觀結構新型鈦合金提出了新的設計思路，并且有可能產生新的機械性能。另外，為了擴展超細、超均勻鈦合金微觀結構的溫度及成分發生范圍，基于存在的熱力學數據庫，Fraser等人提出了一種通過預先預相分離來產生成分和結構不均勻，進而改進鈦合金微觀結構的新方法，我們基于熱力學數據庫和相場動力學的計算機模擬證明其存在。本文中，我們對集成計算材料工程方法在提高設計與選擇具有超細、超均勻微觀結構的鈦合金的效率方面進行了評論總結，集成計算材料工程為鈦合金的開發設計提供了新的思路。

Abstract:

In this paper we review integrated CAPHAD and phase field modeling with critical experiments to explore a newly discovered, non-conventional, solid-solid phase transformation pathway based on the so-called pseudo-spinodal mechanism. This mechanism was first proposed by Ni and Khachaturyan to explain the chessboard structure and then was used by Fraser et al to explain the formation of refined alpha microstructure in Ti-alloys. We show that this new transformation pathway offers a new design strategy for Ti alloys to obtain extremely fine and uniform?????microstructures that could potentially have highly attractive balances of mechanical properties. To broaden the processing window for such a mechanism to operate, a different non-conventional transformation pathway that involves precursory phase separation was reviewed as well.