【摘要】：研究了激光焊接熱輸入對納米析出強化鋼焊接接頭熔深、顯微組織及納米力學(xué)性能的影響。利用體視顯微鏡和掃描電子顯微鏡對焊接接頭的熔深、顯微組織進(jìn)行了分析,通過納米壓入實驗對激光焊接接頭各區(qū)域的納米硬度和彈性模量進(jìn)行了研究。實驗結(jié)果表明:隨著焊接熱輸入增加焊縫熔深逐漸增大,兩者之間呈一元線性關(guān)系;當(dāng)焊接熱輸入低于94 J/mm2時,焊縫為全馬氏體組織;當(dāng)焊接熱輸入超過125 J/mm2時,焊縫中出現(xiàn)貝氏體組織和鐵素體組織;且隨著熱輸入的增加,貝氏體和鐵素體含量有所增加。隨著焊接熱輸入的增加,焊縫區(qū)的納米硬度逐漸降低,其原因為熱輸入增大致使貝氏體和鐵素體的形成。焊接熱輸入對焊縫的彈性模量影響不明顯,彈性模量在200 GPa左右。
[Abstract]:The effects of laser welding heat input on the penetration depth, microstructure and mechanical properties of the welded joints of nanocrystalline precipitated strengthened steel were studied. The penetration depth and microstructure of the welded joints were analyzed by stereoscopic microscope and scanning electron microscope. The nano-hardness and elastic modulus of laser welded joints were studied by nano-indentation experiment. The experimental results show that the weld penetration increases gradually with the increase of welding heat input, and the relationship between them is linear, and when the welding heat input is less than 94 J/mm2, the weld is a martensite structure. The bainite and ferrite structure appeared in the weld when the welding heat input was more than 125 J/mm2, and the content of bainite and ferrite increased with the increase of heat input. With the increase of welding heat input, the nano-hardness of weld zone decreases gradually, which is due to the formation of bainite and ferrite due to the increase of heat input. The influence of welding heat input on the elastic modulus of weld is not obvious, and the elastic modulus is about 200 GPa.
【作者單位】： 安徽工業(yè)大學(xué)冶金工程學(xué)院;蘇州大學(xué)沙鋼鋼鐵學(xué)院;蘇州大學(xué)機電工程學(xué)院激光加工中心;
【基金】：國家自然科學(xué)基金資助項目(51305285) 江蘇省基礎(chǔ)研究計劃(自然科學(xué)基金)(BK20130315) 江蘇省光子制造科學(xué)與技術(shù)重點實驗室開放基金資助項目(GZ201304)
【分類號】：TG407

【共引文獻(xiàn)】

相關(guān)博士學(xué)位論文 前10條

1 崔澤琴;AZ31B鎂合金脈沖激光加工行為的研究[D];太原理工大學(xué);2011年

2 楊t，

本文編號：2321969