Solder powder reflow temperature compared to liquidus temperature

[EIJPN]

I recently started soldering for the first time and I am having some trouble finding the time and temperature that will reflow the solder powder I have. I got a powder of Sn64Bi35Ag1. The product information listed the Solidus Temperature as 151C and the Liquidus Temperature as 172C. (For what it is worth, the density is 8.2 g/cm3)

Can anyone provide advice on what temperature I should heat the solder powder for, and for how long? So far I have tried 1 minute at 160C, followed by 1 minute at 180C; 1 minute at 160C, followed by 2 minutes at 180C; 1 minute at 160C, followed 1 Minute at 200C but the powder is still mostly loose. I have tried rapid cooling, and slow cooling.

In Table 8 of this document, it says for the Reflow profile of SnBi-SnBiAg, the Total time to peak is 215s and Time above 138°C (which I assume is the melting temperature?) is 59s, and that the Peak temperature is 177°C - does this indicate that my attempts were over too short a time frame? If the Liquidus Temperature for my solder powder is listed as 172C, what kind of temperature should I be subjecting it to in order to get it to reflow, and for how long?

 

[3DDave]

Mislabeled or no flux, so the powder is oxidized. I haven't seen use for powder alone; only paste with the flux.

 

[EIJPN]

@3DDave does mixing the powder with flux change the reflow time and temperature?

 

[3DDave]

It should not.

 

[IRstuff]

The flux prevents and breaks down the oxides, doesn't it? To that end, the flux should make it easier for the solder to flow.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm