掃描隧道顯微鏡研究①
(清華大學(xué)材料科學(xué)與工程系，北京100084)
摘 要: 首次用掃描隧道顯微鏡(STM)觀察了Cu-Zn-Al合金的貝氏體和馬氏體表面浮突，發(fā)現(xiàn)貝氏體浮突是由許多亞單元組成的浮突群，單個(gè)亞單元浮突呈“V”型，不同于馬氏體相變不變平面應(yīng)變的“N”型浮突，從而說(shuō)明貝氏體不可能切變形成。同時(shí)在實(shí)驗(yàn)結(jié)果的基礎(chǔ)上，提出了貝氏體激發(fā)形核-臺(tái)階生長(zhǎng)的形成機(jī)制。
關(guān)鍵字: 貝氏體 表面浮突 亞單元 激發(fā)形核 臺(tái)階
AND MARTENSITE TRANSFORMATIONS IN Cu-Zn-Al
ALLOYS WITH SCANNING TUNNELING MICROSCOPY
（Department of Materials Science and Engineering,
Tsinghua University, Beijing100084）
Abstract:Surface reliefs with bainite and martensite transformations in Cu-Zn-Al alloys have been investigated with scanning tunneling microscopy (STM). It was discovered that the surface relief of bainite is actually flocks of reliefs of subunits and the surface relief of each bainite subunit is tent-shaped, which is different from the N-shaped(IPS) surface relief of martensite. So bainite can t be formed by shear. On the basis of the experimental results, sympathetic nucleationledgewise growth mechanism of bainite was proposed.
Key words: bainite surface relief subunit sympathetic nucleation ledge
