416 STAINLESS STEEL
Stainless steel is an irreversible modern alloy of today's economy. Its distinguishing characters restore applications in the era of industrial engineering. Stainless steel is a recycled considerable amalgamation.
Stainless steel alloys are distinguished by the occurrence of chromium that offers superior corrosion resistance. Stainless steel contains 10.5% chromium at least. Levels of chromium, with additional alloying agents like molybdenum, nickel, titanium, etc determine the mechanical properties of stainless steel.
400 series includes Ferritic and Martensitic steel. Grade 410 is martensitic stainless steel.
Martensitic stainless steel is a high carbon, plain chromium steel with 12-18% chromium. It contains high carbon than ferritic or austenitic stainless steel. It offers strength, moderate corrosion resistance, and wear resistance. Martensitic stainless steel shows good ductility and machinability.
GRADE 416
Grade 416 is known for its machinability in all stainless steel around. It is a free-machining grade with improved machinability of 85%. Grade 416 is chromium stainless steel with the addition of sulfur. Grade 416 attains good strength, toughness, and ductility. Mechanical properties of grade 416 can be enhanced by heat treatment. It can be hardened and temper to improve toughness. Grade 416 has excellent machinability, non-seizing, and non-galling properties. It exhibits good oxidation coupled with high strength in the hardened and tempered condition. It is used often in applications that require extensive machining with corrosion resistance. Most widely used in the manufacturing of motor parts, pumps, screw machine parts, etc.
It provides better machining properties than austenitic grades but offers lower corrosion resistance.
COMPOSITION
Grade 416 is plain chromium steel with 12-14% chromium. It also contains nickel, silicon, manganese, and sulfur. The addition of sulfur improves machining abilities drastically by forming manganese sulfide.
The presence of sulfur restricts formability and weldability.
PHYSICAL PROPERTIES
Grade 410 attains a metric density of 7.80 g/cm3.
The modulus of elasticity is 200Gpa.
Electrical resistivity is 57 Microhm-cm.
THERMAL PROPERTIES
Thermal expansion coefficient is 9.9 µm/m° at 1-100°C and
Thermal conductivity is 24.9 W/mK at 100°C and 28.7 W/mK at 500°C.
MECHANICAL PROPERTIES
In annealed conditions, Grade 416 attains a tensile strength of 517 Mpa and yield strength of 275 Mpa. Hardness is 82B. Elongation is 30% in 50mm.
MAGNETIC PROPERTIES
Grade 416 is ferromagnetic in annealed and heat-treated conditions.
HEAT TREATMENT
Annealing
Annealing can be done at between temperature ranges of 815-900°C, followed by air-cooling.
Hardening
Hardening can be attained by heating in the temperature range of 925 to 1010 °C followed by quenching and tempering. Mechanical properties improvised by quenching and tempering.
Tempering
Tempering can enhance mechanical properties. Material is soaked for at least one hour and then cooled in air. Tempering can be done at a temperature between 650°C-750°C but suggested to avoid between the ranges of 400 to 580°C. Tempering at the range may lead to a decrease in impact and corrosion properties
PROPERTIES
CORROSION RESISTANCE
Grade 416 offers considerable resistance to acids, alkalis, fresh water, and dry air. Corrosion resistance can be improved by hardening and polishing. Grade 416 is less corrosion resistant than austenitic grades.
Grade 416 stainless steel is not suitable for chloride and marine environment, as it contains sulfur.
HEAT RESISTANCE
Grade 416 stainless steel offers a scaling resistance of 760°C in intermittent conditions and 675°C in continuous operations.
Grade 416 stainless steel should not be exposed to a temperature greater than the tempering temperature.
WELDING
Grade 416 stainless steel shows poor weldability. Welding can be done by preheating the material to 200 to 300 °C. Then re-hardening and annealing are done at 650-675 °C.
Alloy 410 low hydrogen electrodes are appropriate for welding if needed.
MACHINABILITY
Grade 416 offers the highest machinability in all available steels in the sub-critical annealed condition.
APPLICATIONS
Grade 416 stainless steel is used in end products that required high machinability and corrosion resistance. Grade 416 stainless steel is commonly used for the following application:
- Cutlery and kitchen utensils
- Steam and gas turbine blades
- Fasteners
- Bushings
- Nuts, bolts, screws,
- Pump shafts and valve components
- Washing machine components
- Studs and gears
Ambica steels offer superior fine quality grades 416 bars. Bars are available in round, square, flat, hexagonal, and customized shapes. Inquiry and orders are welcome.
