Automobile cooling system component

A heat exchanger for dissipating heat from a fluid that cools an exothermic body;

• comprising:
• a plurality of tubes through which a fluid circulates, and
• header tanks arranged on both ends in the lengthwise direction of the tubes that communicate with the plurality of tubes by extending in a direction perpendicular to the lengthwise direction of the tubes, and
• the header tanks have a core plate to which the plurality of tubes are joined, and a plastic tank body composing a tank internal space along with the core plate;
• wherein,
• the tank body is composed of a polyamide composition containing polyamide 6,10, glass fiber, a copper compound and at least one type of nucleating agent,
• the polyamide composition contains, based on the total weight of the polyamide 6,10, the glass fiber, the copper and the nucleating agent,
• (a) 48.9 to 79.988 percent by weight of the polyamide 6,10,
• (b) 20 to 50 percent by weight of the glass fiber,
• (c) 0.002 to 0.1 percent by weight of the copper compound, and
• (d) 0.01 to 1.5 percent by weight of the nucleating agent,
• the half-crystallization time of the polyamide composition is 5 minutes or less,
• the polyamide 6,10 used has a relative viscosity, as measured in 98 percent sulfuric acid, of 2.3 to 2.9, and
• the polyamide composition contains, as a polyamide, only the polyamide 6,10.