Which filler metal is known for corrosion and heat resistance and is used as brazing filler for stainless steel, carbon steel, copper, and nickel alloys?

• A. Nickel (Ni)
• B. Silver (Ag)
• C. Tin (Sn)
• D. Aluminum (Al)

Answer: (A)

When choosing a brazing filler metal for joints that may be stainless steel, carbon steel, copper, and nickel alloys, you want something that stands up to corrosion and high temperatures while bonding well to all those substrates. Nickel-based filler metals fit that need best. They offer excellent corrosion resistance and maintain strength at elevated service temperatures, and their chemistry bonds reliably with stainless steel, carbon steel, copper, and nickel alloys, creating durable joints across a wide range of environments. This compatibility helps prevent weakness or premature failure from oxidation or heat.

Other fillers don’t cover all those bases as effectively. Silver-based fillers wet well and perform well at moderate temperatures, but they don’t match nickel-based alloys for high-temperature service and aggressive corrosion resistance. Tin-based fillers are often limited in strength and heat resistance, making them less suitable for high-temperature or highly corrosive applications. Aluminum fillers are used for aluminum-to-aluminum work and aren’t appropriate for the stainless, carbon, copper, and nickel substrates described.