1, hopena hoʻohenehene piʻina

Ke hoʻoheheʻe a komo i loko o ka mea hoʻoheheʻe wela i ka papa hao o ka PCB i ka soldered, ua kapa ʻia ia he mea hiki ke hoʻopaʻa i ka hao a i ʻole ka hoʻopaʻa hao. ʻO nā kinikini o ka hui ʻana o ka solder a me ke keleawe e hana i kahi mea hou he hapa keleawe a me kahi ʻāpana. Kapa ʻia kēia hana hoʻoheheʻe. Hana ia i kahi pilina intermolecular ma waena o nā ʻāpana like ʻole o ka PCB, e hana ana i kahi hui paʻa metala. ʻO ke kūkulu ʻana i nā paʻa intermolecular maikaʻi ke kumu o ke kaʻina hana PCB, kahi e hoʻoholo ai i ka ikaika a me ka maikaʻi o nā helu kuʻihao PCB. Hiki ke pelapela ʻo Tin wale nō inā ʻaʻole manuahi ka pā keleawe a me ke kiʻi ʻoniʻoni i hana ʻia ma muli o ka hōʻike ʻana o PCB i ka lewa, a ʻo ka mea hoʻoheheʻe a me ka pae hana e pono ai i ka mahana kūpono.

2. ʻ tensionkehu alo

Kamaʻāina nā poʻe āpau me ka haunaele o ka wai, ka ikaika e mālama ana i nā kulu wai anuanu ma ka papa metala PCB hamo ʻia no ka mea, i kēia hihia, ʻo ka adhesion e hoʻoliʻiliʻi i ka wai ma kahi papa paʻa ma lalo o kāna hoʻohui. E holoi me ka wai mehana a me ka mea holoi e hoʻoliʻiliʻi i ka haunaele o luna. Hoʻopiha ka wai i ka pā metala PCB hamo a kahe i waho e hana i kahi papa lahilahi, a laila inā ʻoi aku ka nui o ka adhesion ma mua o ka cohesion.

ʻOi aku ka cohesive o ka solder kēpau ma mua o ka wai, e hana ana i ka spherical solder e hoʻoliʻiliʻi i kona ʻilikai (no ka leo like, aia ka sphere i ka ʻāpana o ka ʻāpana liʻiliʻi e hoʻohālikelike ʻia me nā geometry ʻē aʻe e kū i nā koina o ka mokuʻāina ikehu haʻahaʻa loa). ʻO ka hopena o ka flux e like me ka detergent ma ka pā metala PCB i uhi ʻia me ka momona. Hoʻohui, hilinaʻi nui ka ʻenekini i ka maʻemaʻe a me ka mahana o ka ʻili PCB. Aia wale nō a ʻoi aku ka nui o ka ikehu adhesion ma mua o ka ikehu o ka ʻili (cohesion), hiki i ka PCB ke loaʻa i ka adhesion tin.

3, me ka huina Tin

Hoʻokumu ʻia kahi meniskus ke kau ʻia kahi kulu o ka solder ma ka ʻili o kahi PCB wela a me flux i uhi ʻia ma kahi o 35 ° C ma luna aʻe o ka eutectic point of solder. I kekahi mau mea, hiki ke loiloi i ka hiki o ka metala o ka PCB e hoʻopili i ka pi e ke ʻano o ka meniskus. ʻAʻole hiki ke hoʻoheheʻe ʻia ka hao inā he ʻoki maopopo loa ko ka meniskus, e like me nā droplets o ka wai ma kahi pā metala PCB i hamo ʻia, a i ʻole ʻano spherical paha. ʻO ka meniskus wale nō i kau ʻia i ka nui ma lalo o 30. ʻO ka Angle liʻiliʻi he weldability maikaʻi.

4. Ka hanauna o nā mea hoʻohui oka hao

ʻO nā pilina intermetallic o ke keleawe a me ke kin e hana i nā hua a ʻo ka nui a me ka nui e pili ana i ka lōʻihi a me ka ikaika o ka mahana i hoʻopaʻa ʻia ai lākou. Hiki i ka liʻiliʻi o ka wela i ka wā o ke kuʻihao ke hana i kahi hanana aniani maikaʻi, kahi e hana ai i ka PCB i kahi kuʻina maikaʻi me ka ikaika ʻoi loa. ʻO ka lōʻihi o ke ʻano o ka hopena, inā ma muli o ka lōʻihi o ka hoʻopili ʻana o PCB i lōʻihi loa, kiʻekiʻe o ke anawela a i ʻole ʻelua, e hopena i kahi hanana crystalline paʻakikī e maʻalahi a palupalu me ka ikaika haʻahaʻa.Hoʻohana ʻia ke keleawe e like me nā mea metala kumu o PCB, a hoʻohana ʻia ke kēpau-kēpau e like me ke oka solder. ʻAʻole e hana ke kēpau a me ke keleawe i nā mea hoʻohui oka hao, akā hiki i ka pi ke komo i loko o ke keleawe. ʻO ka pilina intermolecular ma waena o ka pi a me ke keleawe e hana i nā mea hoʻohui hao metala Cu3Sn a me Cu6Sn5 ma ka solder a me ka hui metala.

Pono e lahilahi ka papa hana hao (n + ε pae). I ka PCB kukuna kuʻihao, ka mānoanoa o nā mea hiki ke hoʻoheheʻe ʻia he 0.1mm i ka papa helu. I ka soldering nalu a me ka soldering manual, ʻo ka mānoanoa o ka hoʻopaʻa intermetal o nā helu kuʻihao maikaʻi o PCB ma mua o 0.5μm. Ma muli o ka emi ʻana o ka ikaika shear o nā wili PCB i ka hoʻonui ʻana o ka mānoanoa o ka ʻāpana metala, ua hoʻāʻo pinepine ʻia e mālama i ka mānoanoa o ka ʻāpana metala ma lalo o 1μm e ka mālama ʻana i ka manawa kuʻihao i ka wā hiki.

Ka mānoanoa o ka mea hiki ke hooheheeia oka hao e pili ana i ka mahana a me ka manawa o ka hoʻokumuʻana i ka wahi kuʻihao. ʻO ke kūpono, pono e hoʻopau i ke kuʻina ma kahi o 220 ‘t 2s. Ma lalo o kēia mau kūlana, hana ka hopena diffusion o ke keleawe a me ke kēpau i nā mea paʻa paʻa paʻa paʻa Cu3Sn a me Cu6Sn5 me ka mānoanoa o ma kahi o 0.5μm. ʻO ka lawa pono ʻole o ka hoʻopili intermetal ka mea maʻamau i nā hono anuanu a i ʻole nā ​​hono i hoʻoulu ʻole ʻia i ka mahana kūpono i ka wā o ke kuʻihao a hiki ke alakaʻi i kahi ʻoki o ka ʻili weld PCB. I ka hoʻohālikelike ʻana, ʻo nā papa hao paʻa mānoanoa, maʻa mau i nā ami overheated a i hoʻopaʻa ʻia paha no ka lōʻihi, e hopena i ka ikaika loa o ka ikaika o nā hono PCB.