随着用(yòng)于無鉛焊接的高錫焊料合金的出現，銅溶解帶來的挑戰也接踵而至。銅溶解或銅厚度減少會出現在熱風焊料均塗 (HASL) 或長(cháng)時間在高溫下焊接的情況下。Alpha 的錫銅焊料中(zhōng)加入了專門用(yòng)于降低銅溶解的添加劑。

銅溶解工(gōng)藝取決于溫度和焊料合金。銅在錫成分(fēn)至少為(wèi) 95% 的無鉛合金中(zhōng)的可(kě)溶性很(hěn)有(yǒu)可(kě)能(néng)大于在錫鉛焊料中(zhōng)的可(kě)溶性。Alpha 意識到了與該缺陷相關的潛在的可(kě)靠性問題，開發出了一系列能(néng)夠最大程度降低銅溶解的無鉛合金，從而提高了形成的每一個焊點的可(kě)靠性。

可(kě)減少銅溶解的 Alpha 産(chǎn)品：

Alpha 焊條合金

使用(yòng)下圖确定哪種 Alpha 合金适合您。隻需将進行組裝(zhuāng)的類型與适當的合金對應起來即可(kě)。

Assembly Type

I

II

III

IV

Simple, single sided, FR2 / CEM-1 laminates

Dual sided FR-4 w/ PTH's, 1.6mm thick, up to 4 inner copper layers, metallized pad finishes

Complex, up to 12 inner copper layers, OSP pad finishes, all processing in air

>2.4mm thick, >12 inner copper layers, large high heat capacity components

SACX Plus 0807

1%+ flux solids, L0, pin testable

Flux Type

SACX Plus 0307

4%+ flux solids, L or M0, pin testable

SnCX Plus™ 07

4%+ flux solids, L or M0, moderately pin testable

7%+ flux solids, L,M or H1, not pin testable

0ºC to 100ºC - standard profile cycles

0ºC to 100ºC - standard and shock profile cycles

- 25ºC to 125ºC - standard and shock profile cycles

- 45ºC to 125ºC - standard and shock profile cycles

Thermal Fatigue Resistance