By changing thickness of the crazes with temperature,the burning area of the propellant is changed.A compensating system is founded in two-layered variable-burning rate propellant and low temperature coefficient of the propellant is realized.The craze and thickness of craze changing with temperature were observed by means of SEM;The combustion character of two layered variable-burning rate propellant at high,low and normal temperature was obtained by the closed bomb test.The interior ballistic performance o...