Abstract: An integrated cooling system for a fuel cell vehicle according to this invention comprises a fuel gas flow field for supplying fuel gas to a fuel cell stack and exhausting the fuel gas from the fuel cell stack through a fuel gas accumulator, and an air flow field for supplying air to a fuel cell stack and exhausting the air from the fuel cell stack through an air accumulator, wherein at least one cooling pipe of the cooling system comprises a plurality of heat-dissipation pins on a circumferential surface thereof.

Abstract: A sintered alloy having an improved wear resistance and a workability for a valve seat. The alloy contains iron as a main component, carbon, silicon, chromium, molybdenum, cobalt, maganese, lead, vanadium, advantageously boron nitride, and tungsten. The strength, wear resistance, and material properties are improved by a sub-zero treatment. Sintered alloy with wear resistance used for a valve seat comprises Fe as a main component, C of 1.2 to 1.7 wt %, Cr of 3.5 to 5.0 wt %, Mo of 2.0 to 4.0 wt %, V of 3.0 to 5.0 wt %, W of 7.0 to 10.0 wt %, Co of 2.0 to 3.5 wt %, boron nitride of 0.1 to 1.0 wt %, S of 0.2 to 0.4 wt %, Mn of 0.2 to 0.5 wt %, advantageously 0.2 to 0.6% Si, and Pb of 10.0 to 15.0 wt %. Sintered alloy for an valve seat is manufactured by a sub-zero treatment so that the amount of metallic particles separated from a base matrix decreases and a size of the separated metallic particle becomes small.