Phase diagram and heterophase structure of the K2Cd2xMn2(1-x)(SO4)3 solid solutions

K2Cd2xMn2(1-x)(SO4)(3) solid solutions with x = 0 similar to 1 were grown with a step Delta x = 0.1 by Czochralski and Brid,oman methods. Ferroelastics phase transitions were investigated by optical birefringence, dielectric and optical microscopy methods. The concentration-temperature phase diagram was obtained. The isolated point of the second order phase transition (x(i) = 0.8; T-i = 358 K) has been found in the line of the first order phase transitions. The existing of the heterophase structure in all solid solutions was found below T-c. In this structure the regions of paraelastic phase is separate two orientational stales and such structure is a property of the ferroelastics phase transitions with non-permissible domain walls.