The main function of an injection mold‚ besides defining a part's shape‚ is to remove heat from the plastic as quickly as possible. The mold should be thought of as a heat transfer device much like the automobile radiator shown above. The faster the mold can transfer heat out of the molten plastic and solidify it‚ the faster the mold can be run. Reduced cycle time equates to reduced manufacturing cost. This is where copper alloys outperform other metals used for molds. Copper alloys provide the best combination of high thermal conductivity and hardness for molds used in the plastic industry today. As seen in the Comparison of Mold Alloy Properties Table‚ hardness and conductivity vary over a range for each alloy system–steel‚ aluminum‚ or copper. Copper alloys have thermal conductivities 3 to 9 times greater than the commonly used Type 420 stainless steel

Additional Copper Alloy Mold Information

• Copper Advantage
• Cooling Prediction of Non–Watered Copper and Steel Mold Cores
• Getting Heat Out of the Mold Where Water Won't Go
• Whirlpool Uses Copper Alloy Mold for Dishwasher Console Part

ANTEC Reports

• Undercutting Mold Performance: Ejection Wear
• Size Does Matter: Minimization Of Gate Wear
• Use Of Copper Alloys To Reduce Mold Condensation Problems
• Impact Of Fines Separation On Reinforced Thermoplastic Regrind
• Comparison Of Various Hard Coatings To Protect Copper Mold Components From Erosive Wear
• Resistance To Erosive Wear By Copper Alloy Mold Components
• Understanding The Source Of Reduced Mechanical Properties In Reinforced Molded Products

This publication, based on available data, has been prepared for the information and use of professionals in the industry. CDA assumes no responsibility or liability in connection with this publication and makes no warranties of any kind with respect to the information contained herein.

This information was provided with permission by the Copper Development Association at www.copper.org