Technical details and how to build an ultrasonic soldering iron. This technique can bond difficult-to-solder metals such as titanium as well as glass and ceramics.

Cerasolzer technical info: http://cerasolzer.com/cerasolzer/basic_info_gb.html

S-bond technical info: https://www.s-bond.com/solutions-and-service/ultrasonic-soldering/ultrasonic-solder-materials/

Overview of active soldering process: https://sci-hub.tw/10.5772/intechopen.82382

Another good overview: https://www.intechopen.com/books/recent-progress-in-soldering-materials/recent-advances-in-solderability-of-ceramic-and-metallic-materials-with-application-of-active-solder

Discussion of Sn - La solders: https://www.hindawi.com/journals/amse/2015/269167/

Sn - Ti phase diagram: https://sci-hub.tw/https://doi.org/10.1007/s11669-010-9663-2

This patent has the key list of ingredients (not just broad ranges) listed at paragraph 45: https://patents.google.com/patent/US20160204303A1/en

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