Magnetic properties and magnetocaloric effects in Er1-xGdxCoAl intermetallic compounds

The magnetism and magnetocaloric effect in Er1-xGdxCoAl (x = 0, 0.1, 0.2, 0.4, 0.6, 0.8, 1) were investigated. The Er1-xGdxCoAl compounds were synthesized by arc melting. With the increasing Gd content, the Neel temperature (T-N) linearly increases from 14 K to 102 K, while the magnetic entropy change (-Delta S-M) tends to decrease nonmonotonously. Under the field change from 0 T to 5 T, the D SM of the compounds with x = 0.2-1 are stable around 10 J/kg . K, then a cooling platform between 20 K and 100 K can be formed by combining these compounds. For x = 0.6, 0.8, 1.0, the compounds undergo two successive magnetic transitions, one antiferromagnetism to ferromagnetism and the other ferromagnetism to paramagnetism, with increasing temperature. The two continuous magnetic transitions in this series are advantageous to broaden the temperature span of half- peak width (delta T) in the -Delta S-M-T curve and improve the refrigeration capacity.