"on amicable terms" is correct and usable in written English. It is used to describe a situation in which two people are interacting peacefully and without any hostility. For example: The two former friends left the argument on amicable terms.
The pair will separate on amicable terms.
After some photographs by the River Mersey, we part on amicable terms.
Mr. Makem left the Clancy Brothers on amicable terms in 1969 to have a solo act.
She was the mother of 9-year-old twins, having divorced her husband Michel Nogues in 1967 on amicable terms.
Jimmy Carter and Gerald R. Ford seem to be on pretty amicable terms these days despite their own close election in 1976.
It looks like the departure is on fairly amicable terms: the internal memo published in the blog post mentions that it will toast Doll at the company's Friday "Mock-o-Clock" meeting.
From the time when he and Elizabet had separated two years earlier, on the most amicable terms, the boy had lived with his father and spent every other day at his mother's house.
Being a terminologist, I care about word choice. Ludwig simply helps me pick the best words for any translation. Five stars!
Maria Pia Montoro
Terminologist and Q/A Analyst @ Translation Centre for the Bodies of the European Union