Some care needs to be taken in working with phosphor bronze,
particularly when cutting or grinding it.  The fumes (presumably from
heating it) or dust and fine particles from grinding are highly
irritating to the lungs and must be avoided.  Here's a link to the
material safety data sheet:

http://www.ifa.hawaii.edu/instr-shop/MSDS/Phosphor%20Bronze%20Alloys.pdf 

John Grant