Blockade® is a silicon brazing alloy that the company says marks a turning point in industrial metal-joining technology for copper-to-copper and copper-to-brass connections. Patent-pending Blockade is said to be a more cost-effective alloy, easier to use, and practically leak-proof.
According to the company, the product quickly and easily builds and maintains a large, silvery "cap" while filling the capillary of the connection at the same time. The bright Blockade braze cap is said to be easy to see, so an incomplete braze is noticed and can be corrected while still in production and before a leak can occur. This cap forms a 100-percent seal that is strong and leak-proof. The product reportedly melts at a lower brazing temperature (228°F lower) than other brazing alloys, making it faster and more economical. It does not require pre-cleaning or flux on copper. It brazes brass, yet contains no silver.
J.W. Harris Co., Inc.