The tension–tension and compression–compression cyclic properties are measured for an open cell “Duocel” foam of composition Al 6101–T6, and a closed cell “Alporas” foam of composition Al–5Ca–3Ti (wt%). The Duocel foam has a relatively uniform microstructure, and undergoes homogeneous straining in both monotonic and fatigue tests. In contrast, the Alporas foam is more irregular in microstructure, and exhibits crush-band formation at random locations under uniaxial compression; in compression–compression fatigue, a single crush band forms and broadens with additional fatigue cycles. Progressive shortening of the specimen in compression–compression fatigue, and progressive lengthening in tension–tension fatigue are due to a combination of low cycle fatigue failure and cyclic ratchetting. S–N fatigue curves are presented for the onset of progressive shortening in the compression tests, and material separation in the tension tests; it is envisaged that such curves will be of practical use in design.