Cov teeb meem tshwm sim hauv Magnesium Alloy Vuam

(1) Coarse Crystal

Magnesium muaj qhov qis melting point thiab siab thermal conductivity. Yuav tsum muaj lub zog vuam hluav taws xob siab thaum vuam. Qhov chaw weld thiab ze-seam yog qhov ua rau overheating, grain loj hlob, siv lead ua segregation thiab lwm yam tshwm sim, uas txo cov kev sib koom ua ke.

(2) Oxidation thiab evaporation

Magnesium yog oxidizing heev thiab yooj yim ua ke nrog oxygen. Nws yog ib qho yooj yim los tsim MgO thaum lub sij hawm vuam txheej txheem. MgO muaj lub siab melting point (2 500 ℃) thiab siab ceev (3. 2 g / cm-3), thiab nws yog ib qho yooj yim rau tsim me me flakes nyob rau hauv lub weld. Cov khoom slag suav nrog tsis tsuas yog cuam tshuam qhov tsim ntawm cov vuam, tab sis kuj txo qhov kev ua haujlwm ntawm vuam. Thaum lub vuam kub kub, magnesium tuaj yeem yooj yim ua ke nrog nitrogen hauv huab cua los tsim magnesium nitride. Magnesium nitride slag suav nrog kuj tseem yuav ua rau txo qis hauv plasticity ntawm cov hlau vuam thiab ua rau kev sib koom ua haujlwm tsis zoo. Lub boiling point ntawm magnesium tsis siab (1100 ℃) thiab nws yog ib qho yooj yim rau evaporate nyob rau hauv lub kub kub ntawm arc.

(3) Hlawv los ntawm thiab tawg ntawm nyias qhov chaw

Thaum welding nyias qhov chaw, vim qhov tsawg melting point ntawm magnesium alloy thiab siab melting point ntawm magnesium oxide, ob yog tsis yooj yim fused, ua rau nws nyuaj rau soj ntsuam cov txheej txheem melting ntawm lub vuam seam thaum lub sij hawm vuam ua hauj lwm. Raws li qhov kub thiab txias, cov xim ntawm lub pas dej molten tsis hloov pauv loj, ua rau nws kub hnyiab thiab tawg.

(4) Kev kub ntxhov thiab tawg

Magnesium thiab magnesium alloys muaj cov coefficient siab ntawm thermal expansion, kwv yees li ob zaug ntawm cov hlau thiab 1 Ob zaug, nws yog ib qho yooj yim los ua kom muaj kev ntxhov siab thiab deformation thaum lub sij hawm vuam. Magnesium yooj yim tsim cov ntsiab lus qis melting eutectic nrog qee cov ntsiab lus alloying (xws li Cu, Al, Ni, thiab lwm yam) (xws li Mg Cu eutectic kub ntawm 480 ℃, Mg Al eutectic kub ntawm 430 ℃, Mg Ni eutectic kub ntawm 508 ℃) , nrog rau qhov dav ntawm qhov kub thiab txias thiab yooj yim tsim ntawm kub tawg. Kev tshawb fawb tau pom tias thaum w (Zn)> 1%, nws nce thermal brittleness thiab tuaj yeem ua rau vuam tawg. Ntxiv w (Al) ≤ 10% rau magnesium tuaj yeem kho qhov loj ntawm cov vuam thiab txhim kho weldability. Magnesium alloys uas muaj me me ntawm Th muaj qhov zoo weldability thiab tsis nyiam tawg.

(5) Stomata

Hydrogen pores tau yooj yim tsim thaum lub sij hawm magnesium vuam, thiab solubility ntawm hydrogen nyob rau hauv magnesium kuj txo sharply nrog txo kub.

(6) Magnesium thiab nws cov alloys yog nquag oxidation thiab combustion thaum vuam nyob rau hauv ib puag ncig huab cua, thiab yuav tsum tau inert roj los yog flux tiv thaiv thaum lub sij hawm fusion vuam ·