AMF wore a Union Jack Patch when first formed in the 1960's as well as a Enamel Fob Badge. I wore the UJ at 9 Field Workshops REME (RAOC Section) in 1976 and the Fob Badge only when deployed or on related training.
A later Arm Patch was issued in the 80's
British Forces Embellishments
An earlier meaning is Army Management Fund