In a simulation of a superconducting strand, it is usual to treat the strand as superconducting wire and copper wire in a parallel connection. When simulating a multi-stranded cable, strands are treated as a mixture of superconductor and copper, usually. All parameters are calculated from combination of those for superconductor and copper. This means the role of copper was just changing properties of the strand. However in real current transition process, copper matrix may play a role of a path of current and heat. In this paper, one strand is considered as two wires; superconductor and copper, and calculations were done for a cable with two strands. The simulation model and some results which show behavior of the copper matrix in quench process are presented in this paper. The difference between 'matrix heating' and 'filament heating' is discussed, also.