As a straight chromium, alloy SST-430 is a ferritic that is non-hardenable, easily formed and resistant to corrosion. It is especially resistant to chemicals such as nitric acid, which makes it ideal for environments where it will come into contact with various chemicals.

The free-machining grade 430F is the grade of SST-430 that is often used for automatic screw machines. Grade 434, with molybdenum is especially resistant to corrosion.

When alloy SST-430 is polished or buffed it is even more resistant to organic acids such as nitric acid. It is also more resistant to stress cracking and corrosion. The high sulphur content of grade 430F makes it more resistant to crevice corrosion and pitting.

Intermittent service to 870 C allows for oxidation resistance, but continual exposure will lower the maximum temperature for oxidation resistance to 815 C. Prolonged exposure to temperature of 400 to 600 C will result in alloy SST-430 becoming brittle, although this tendency can be alleviated through the annealing process.

Thermal treatment will not enable hardening of stainless steel alloy 430. High temperatures are more likely to result in scaling than is SST-304.

Alloy SST-304 should be pre-heated to 200 C before any welding is attempted. To avoid any brittling at the weld or in the area affected by the heat, a post-weld annealing should be performed.

For machining, alloy SST-430F is the best grade for that purpose. Although alloy SST-430 is more easily machined than SST-304, it is still likely to gall and pick up on the cutting tool.

Because of its lower work hardening rate, alloy 430 will form and bend much easier during fabrication than will SST-304. When heavy cold working is performed, an intermediate sub-critical annealing may necessary.

Most commonly SST-430 is used as trim on automobiles and trucks. It is also used for stove-top element supports and trim rings. Additionally dishwasher liners and outer panels for refrigerators are also made using alloy SST-430.

To learn more about the stainless steel alloy SST-430.