PCB sanoati bosilgan elektron jarayonida qo'rg'oshin-qalay qotishma elektrokaplamani joriy etish!
Dec 15, 2021
Elektron platalarni bosib chiqarish jarayonida po'lat chiziqning yuzasi odatda moylash, bog'lash va lehimlash uchun qoplama bosib chiqarish jarayoniga ega. Ushbu jarayon sanoatda qo'rg'oshin-qalay qotishmalarini elektrokaplama sifatida tanilgan. Ushbu maqola qo'rg'oshin-qalay qotishmalarining dielektrik elektrokaplama funktsiyasi va mexanizmini qisqacha tanishtiradi.
Qalayning element belgisi Sn, atom og'irligi 118,7, zichligi 7,29 g/sm3, Sn2 ning elektrokimyoviy ekvivalenti 2,214 g/Ah. Qo'rg'oshin elementining belgisi Pb, atom og'irligi 207, zichligi 11,4 g/sm3, Pb2 ning elektrokimyoviy ekvivalenti 3.865g/Ah.
Qalay-qo'rg'oshin qotishma qoplamasi bosilgan elektron platalarni ishlab chiqarishda gidroksidi bilan ishlov berish uchun himoya qatlamidir. Bunday holda, qoplamadagi qo'rg'oshin tarkibi juda muhim emas. Oshlamadan keyin issiq eritma kerak bo'lganda, 60-63% qalay qo'rg'oshin qoplamasi ta'minlanishi kerak. Qoplama bir xil, nozik, yarim yorqin, qalinligi 8 mikron bo'lishi kerak. Qoplamaning qo'llanilishiga qarab, qoplama to'liq yorqinlikni talab qilmaydi. Kislotali eritmada qo'rg'oshin va qalay elektrodlari o'xshash potentsialga ega va ularni birgalikda joylashtirish oson. Qo'rg'oshin-qalay qotishma qoplamalarining turli nisbatlarini olish uchun qo'rg'oshin va qalay ionlari kontsentratsiyasini va katod oqimining zichligini nazorat qilish mumkin. Ftoroborat vannalari sanoatda keng qo'llaniladi.
The tin-lead alloy plating solution should have good dispersibility and deep plating ability, stable process and easy maintenance. There are many kinds of electroplating solutions, but the main ones are fluoroborate type and non-fluoroalkyl sulfonate type. The fluoride bath is stable, easy to maintain and low cost, and has become the most widely used process in PCB production for many years. However, in recent years, more and more attention has been paid to the pollution of fluoride, and the amount of fluorine-free electroplating solution is also increasing rapidly. Alkyl sulfonic acid tin-lead alloy plating solution has become more and more mature in recent years, and the prices of materials and additives have also become reasonable, and the dosage has increased year by year. At the same time, additives are no longer a single imported product, and the quality and quantity of domestic additives have been significantly improved.
