中国铸造装备与技术
中國鑄造裝備與技術
중국주조장비여기술
China Foundry Machinery & Technology
2014年
4期
54-57
,共4页
袁训锋%杨燕%刘彦峰%汤引生%赵杰%李春%周春生
袁訓鋒%楊燕%劉彥峰%湯引生%趙傑%李春%週春生
원훈봉%양연%류언봉%탕인생%조걸%리춘%주춘생
镁合金%相场法%非枝晶生长%空间步长
鎂閤金%相場法%非枝晶生長%空間步長
미합금%상장법%비지정생장%공간보장
Magnesium alloy%Phase-field method%Non-dendrite growth%Space step
采用相场法对镁合金自孕育半固态浆料制备中非枝晶生长过程进行模拟,研究了空间步长对非枝晶生长行为的影响。结果表明:镁合金多晶粒共同竞争生长时,晶粒形貌由晶体结构特征和生长空间共同决定。晶粒在具有较大生长空间的优先生长方向上,固液界面前沿溶质富集程度低,保持生长优势,形成主枝;晶粒在具有较小生长空间的优先生长方向上,固液界面前沿溶质富集严重,尖端变秃,形成非枝晶形貌。随着空间步长的增加,晶粒合并生长趋势减弱,固液界面前沿溶质富集和溶质偏析程度降低。
採用相場法對鎂閤金自孕育半固態漿料製備中非枝晶生長過程進行模擬,研究瞭空間步長對非枝晶生長行為的影響。結果錶明:鎂閤金多晶粒共同競爭生長時,晶粒形貌由晶體結構特徵和生長空間共同決定。晶粒在具有較大生長空間的優先生長方嚮上,固液界麵前沿溶質富集程度低,保持生長優勢,形成主枝;晶粒在具有較小生長空間的優先生長方嚮上,固液界麵前沿溶質富集嚴重,尖耑變禿,形成非枝晶形貌。隨著空間步長的增加,晶粒閤併生長趨勢減弱,固液界麵前沿溶質富集和溶質偏析程度降低。
채용상장법대미합금자잉육반고태장료제비중비지정생장과정진행모의,연구료공간보장대비지정생장행위적영향。결과표명:미합금다정립공동경쟁생장시,정립형모유정체결구특정화생장공간공동결정。정립재구유교대생장공간적우선생장방향상,고액계면전연용질부집정도저,보지생장우세,형성주지;정립재구유교소생장공간적우선생장방향상,고액계면전연용질부집엄중,첨단변독,형성비지정형모。수착공간보장적증가,정립합병생장추세감약,고액계면전연용질부집화용질편석정도강저。
The non-dendrite growth has been simulated by the phase field method in preparation of self-inoculated Mg alloy semi-solid slurry. The effects of space step on the non-dendrite growth behavior have been studied. The results showed that the crystal morphology has been determined by the structural characteristics and growing space when Mg alloy polycrystal grains were growing competitively. When the preferential growth orientation of crystal grain had larger growing space, solute enrichment degree was low in the front of the solid-liquid interface, the crystal grain grew fast and developed to dendrite trunks. However when the preferential growth orientation of crystal grain had small growing space, solute enrichment degree was high in the front of the solid-liquid interface, the tip became bald and developed to non-dendrite structure. With the increasing of space step, the trend of grain combined growth was weakened, the degree of solute enrichment and segregation decreased in the front of the solid-liquid interface.