Kev tsim cov txheej txheem ntawm tin phosphor bronze

Vim lub siab thermal brittleness ntawm tin phosphor bronze, tam sim no zus tau tej cov tin phosphor bronze daim ntawv thiab sawb cov khoom nyob rau hauv tsev thiab txawv teb chaws feem ntau yog siv kab rov tav nruam casting los tsim ingots, thiab ua hauj lwm mus sij hawm ntev homogenization annealing kev kho mob.
Tom qab txias dov, nruab nrab annealing, pickling, thiab ntxhib thiab tiav dov, lub crystallization kub ntau yam ntawm cov tiav lawm tin phosphor tooj liab yog dav, ntawm 835 thiab 1040 degree, thiab nws tsis yog yooj yim rau tsim concentrated shrinkage kab noj hniav thaum lub sij hawm solidification, thiab nws yog ib qho yooj yim los tsim porosity hauv lub casting.
Vim nws loj crystallization kub ntau, thaum nws nkag mus rau qhov pib crystallization kub, thawj crystallized solid tov maj ua dendrites raws li qhov kub thiab txias, thaum lub tin-nplua nuj melting point (tin melting point yog.
231.89 degree) cov khoom sib xyaw yog yooj yim rau kev sib cais ntawm dendrites lossis ntawm qhov sib txuas ntawm cov nplej uas nyob ib sab, tsim cov xwm txheej rau "rov qab cais tawm" thiab tsim porosity. Kev sib cais rov qab yog ib qho tseem ceeb tshaj plaws hauv cov txheej txheem casting ntawm tin-phosphorus bronze. Nyob rau ntawm ntug thiab saum npoo ntawm lub ingot, cov ntsiab lus ntawm tin thiab phosphorus yog siab tshaj qhov nyob rau hauv nruab nrab ntawm lub ingot. Hauv cov xwm txheej hnyav, grey-dawb precipitates (feem ntau hu ua Tin hws, muaj pes tsawg leeg yog Cu33Sn8 thiab Cu3P
Tsis tas li ntawd, qhov txias hardening tus nqi ntawm cov alloy yog siab, thiab tus naj npawb ntawm annealing nce, uas ua rau lub voj voog ntau lawm.
Ua rau Kev Tshawb Fawb Txog Kev Nyuaj Siab Ntawm Tin Phosphor Bronze
Kev txiav txim los ntawm Cu-Sn equilibrium theem daim duab qhia, lub solidification kub ntawm tin phosphor bronze yog nyob nruab nrab ntawm 150 thiab 160 degree thaum 6 feem pua ​​​​rau 7 feem pua ​​Sn yog muaj. Thaum cov khoom siv lead ua khov kho, nws yuav tsis tsim cov kab noj hniav uas muaj zog, tab sis yuav ua rau cov kab noj hniav tawg los yog cov porosity.
Feem ntau, cov porosities tawg yog txuas nrog thaum dov, uas tsis tshua muaj kev cuam tshuam rau cov tsos thiab kev ua haujlwm. Txawm li cas los xij, nyob rau hauv qee qhov txheej txheem tsis tsim nyog, qhov loj dua lossis cov hlua zoo li cov hlua xoob xoob tuaj yeem tsim, thiab vim tias cov chaw xoob no yog qhov chaw zaum kawg ntawm cov dendrites, qee cov ntsiab lus qis melting yog ib qho yooj yim rau kev sib cais ntawm no. Thaum lub sij hawm dov, lub nraub qaum ntawm lub billet yog raug rau tensile kev nyuaj siab thaum rov qab curling, thiab nws yog ib qho yooj yim rau tawg raws cov xoob cheeb tsam los tsim cov kab nrib pleb. Vim tias qhov diffusion ntawm Sn qeeb heev, kev xaiv crystallization yog ua nyob rau hauv qhov kub thiab txias ntau yam, tsim kev sib cais loj dendrite. Thawj crystallization hauv cov nplej yog cov ntsiab lus siab melting, thiab cov dendrite uas crystallizes tom qab yog cov khoom uas tsis tshua muaj melting point. Qhov tsis sib xws ntawm cov muaj pes tsawg leeg hauv cov nplej yuav ua rau muaj qhov sib txawv loj hauv cov khoom siv kho tshuab, tshwj xeeb tshaj yog cov "cohesive force" ntawm cov dendrites. Tsis muaj zog sab ". Thaum lub sij hawm ua, lub nraub qaum ntawm lub sawb yog pheej rov qab los ntawm tensile kev nyuaj siab, thiab nws yog ib qho yooj yim rau tawg raws cov "tsis muaj zog nto".
Thaum C5191 txias thiab crystallized, vim qhov tsis zoo thermal conductivity, qhov kub sib txawv ntawm sab hauv thiab sab nraud yog loj. Tom qab lub plhaub tawv yog tsim rau ntawm qhov chaw, qhov nruab nrab yog nyob rau hauv lub xeev ua kua. Ib feem ntawm Sn yog extruded los ntawm "channel" mus rau saum npoo raws li thim rov qab cais. Thiab "channel" yog ib qho yooj yim rau cais cov theem tsis sib npaug nrog cov ntsiab lus Sn siab dua, cov theem tsis sib npaug
Qee lub sij hawm yog nkig thiab nyuaj, uas yooj yim rau tawg rau hauv cov kab nrib pleb thaum dov.