Effect of material property, surface temperature and contact duration on the thermal sensation when contacting shell materials of electronic devices.

Heat generated in electronic devices is generally unevenly distributed across the casing. Contacting the hot areas may cause thermal discomfort and possibly skin burn. This study aims at better understanding the interrelationship between the thermal sensation, material properties and surface temperature for enhancing the user experience of electronic devices. A Thermal Simulation System was developed in this study to precisely control the surface temperature of shell materials to simulate various end-use conditions. Seventeen participants were asked to contact the plates with their fingers and rate their thermal sensation using the magnitude estimation approach. Results showed that thermal sensation magnitude and plate temperature followed a power function. The differences in sensation magnitude can be attributed to the thermal inertias of different materials. The findings suggested that laminated plate was generally perceived cooler when heated. Given that the surface temperature of plate is higher than skin, the thermal sensation magnitude increases with contact duration.