PCB nekuda kwekurongeka kwayo uye kuomarara, zvinodiwa zvehutano hwezvakatipoteredza zvese PCB workshop zvakakwirira kwazvo, uye mamwe mashopu anotoonekwa ne "yellow light" zuva rese. Humidity, zvakare chimwe chezviratidzo zvinoda kunyatsodzorwa, nhasi tichataura nezvekukanganisa kwehunyoro paPCBA.
Izvo zvakakosha "humidity"
Humidity chinhu chakakosha uye chakanyatso kudzora chiratidzo mukugadzira maitiro. Hunyoro hushoma hunogona kukonzera kuoma, kuwedzera ESD, kuwedzera guruva mazinga, kuvharika kuri nyore kwekuvhurwa kwetemplate, uye kuwedzera kupfeka template. Kudzidzira kwakaratidza kuti hunyoro hushoma huchakanganisa zvakananga uye kuderedza huwandu hwekugadzira. Kunyanya kukwira kuchaita kuti zvinhu zvitore hunyoro, zvichikonzera delamination, popcorn mhedzisiro, uye solder mabhora. Kunyorova zvakare kunoderedza kukosha kweTG kwechinhu uye kunowedzera iyo inoshanduka warping panguva yekuyerera welding.
Nhanganyaya kune hunyoro hwepamusoro
Zvinenge nzvimbo dzese dzakasimba (senge simbi, girazi, ceramics, silicon, zvichingodaro) dzine danda remvura rinotora mvura (rimwe chete kana akawanda-mamolecular layer) rinoonekwa kana tembiricha yepasi yakaenzana netembiricha yedova remhepo yakatenderedza (zvichienderana nekupisa, mwando, uye mhepo). Kukweshana kuri pakati pesimbi nesimbi kunowedzera nekudzikira kwemwando, uye pakunyorova kwe20% RH zvichidzika, kukwesha kwacho kunokwira ka1.5 pane pahunyoro hwe80% RH.
Porous kana mwando inonwisa nzvimbo (epoxy resins, mapurasitiki, fluxes, etc.) anowanzo tora aya anonwisa akaturikidzana, uye kunyangwe kana tembiricha yepasi iri pazasi pedova (condensation), iyo inonyudza ine mvura haioneki pamusoro pechinhu.
Iyo ndiyo mvura iri mune imwechete-morekuru inonyudza maseru pane aya mapasi ayo anopinda mupurasitiki encapsulation mudziyo (MSD), uye kana imwechete-morekuru inonyudza maseru inosvika makumi maviri muhukobvu, mwando unotorwa neaya mamorekuru anomwisa maseru anozokonzeresa popcorn mhedzisiro panguva yekuyerera solder.
Kufurira kwehunyoro panguva yekugadzira
Humidity ine zvakawanda zvinokonzeresa pakugadzira nekugadzira. Kazhinji, humidity haioneki (kunze kwekuwedzera uremu), asi mhedzisiro ndeye pores, voids, solder spatter, solder mabhora, uye pasi-kuzadza voids.
Mune chero nzira, kutonga kwehunyoro uye kunyorova kwakakosha zvikuru, kana kutaridzika kwemuviri wepamusoro kusiri kwakajairika, chigadzirwa chakapedzwa hachikodzeri. Naizvozvo, iyo yakajairika workshop inofanirwa kuve nechokwadi kuti hunyoro uye hunyoro hweiyo substrate pamusoro inodzorwa nemazvo kuti ive nechokwadi chekuti zviratidzi zvezvakatipoteredza mukugadzirwa kwechigadzirwa chakapedzwa zviri mukati meiyo yakatarwa.
Nguva yekutumira: Mar-26-2024
