【摘要】：高鉻鑄鐵型藥芯焊絲以其優(yōu)異的堆焊性能已廣泛應(yīng)用于各種耐磨粒磨損部件的制造與堆焊修復(fù)中。本文對實(shí)驗(yàn)室自制的金屬粉型高鉻鑄鐵藥芯焊絲的堆焊工藝性能及堆焊層耐磨性能進(jìn)行了分析研究。借助高速攝影機(jī)對藥芯焊絲熔滴過渡過程的拍攝以及水槽法對焊接飛濺顆粒的收集,觀察和研究了高鉻鑄鐵藥芯焊絲的熔滴過渡過程以及焊接飛濺的形式和特點(diǎn);利用磨粒磨損試驗(yàn)機(jī)測試了高鉻鑄鐵堆焊層的耐磨性;采用光學(xué)金相顯微鏡、掃描電鏡、能譜測量儀對高鉻鑄鐵堆焊層組織及磨損試樣的表面磨損狀況進(jìn)行觀察分析。研究結(jié)果表明:(1)研制的高鉻鑄鐵型藥芯焊絲在堆焊過程中有著良好的工藝性能,堆焊焊縫圓滑平整且渣量極少,熔滴過渡過程為穩(wěn)定的大滴排斥過渡,飛濺率較低,在1%左右。(2)小顆粒飛濺(d1mm)是該藥芯焊絲堆焊過程中出現(xiàn)頻率最高的飛濺,易產(chǎn)生于熔滴脫離焊絲端部瞬間和熔滴炸裂瞬間;中等顆粒飛濺(1mm≤d≤2mm)往往產(chǎn)生于熔滴形成初期和熔滴劇烈爆炸的時刻,其在數(shù)量上遠(yuǎn)不及小顆粒飛濺;大顆粒飛濺(d2mm)偶爾出現(xiàn),一般是整個熔滴飛出熔池區(qū)域。(3)高鉻鑄鐵堆焊層在磨粒磨損過程中除了砂帶參與磨損之外,其他磨粒主要還有M7C3型碳化物、鉻的其他碳化物、NbC。焊絲中過量的Nb可能會不利于耐磨粒磨損性能的提高。
[Abstract]:High chromium cast iron flux-cored wire has been widely used in the manufacture and repair of wear resistant wear parts due to its excellent surfacing properties. In this paper, the surfacing technology and the wear resistance of the surfacing layer of the metal powder high chromium cast iron flux cored wire made by ourselves in laboratory are analyzed and studied. The droplet transfer process of high chromium cast iron flux-cored wire and the form and characteristics of welding spatter were observed and studied by means of high-speed camera shooting of flux-cored wire droplet transfer process and the collection of splashing particles by flume method. The wear resistance of high chromium cast iron surfacing layer was tested by abrasive wear tester, and the microstructure and surface wear of high chromium cast iron surfacing layer were observed and analyzed by optical microscope, scanning electron microscope and energy dispersive spectrometer. The results show that: (1) the developed flux-cored wire with high chromium cast iron has good technological properties during surfacing, the weld seam is smooth and the amount of slag is very small, the droplet transfer process is stable and large droplet repulsive transition, and the spatter rate is low. (2) small particle splashing (d1mm) is the most frequent spatter in the surfacing process of the flux-cored wire, which is easy to occur when the droplet is separated from the end of the wire and the droplet burst; The medium particle spatter (1mm 鈮，

本文編號：2411671