Abstract:

To improve thermal protective performance of firefighters’ protective clothing, several shape memory alloy (SMA) springs were arranged between the moisture barrier laet and the thermal insulation inner layer to develop a smart flame resistant fabric combination with a dynamic structure. A low radiant heat was simulated by a thermal protective performance tester and the surface temperatures between layers under exposure to low radiation were recorded. The protective performance of fabric in different arrangement modes of SMA springs was evaluated by the temperature changes between layers. The results indicated that SMA springs have good dynamic heat insulating properties by means of the air layer caused by the deformation of SMA springs under radiant heat, and thus improve the protective performance of fabrics. Meanwhile, the arrangement of SMA springs has impact on the thermal protection as well. The samples with the SMA arrangements of one spring in the center and three springs on the diagonal line exhibit better thermal protection performance. The shape and size of the air gap produced by different arrangements of SMA springs show obvious difference, and thus affect the thermal insulation properties of flame retardant fabric combinations.

Key words: firefighters' protective clothing, shape memory alloy spring, low radiation, thermal insulation performance