Grade 416 steel is a free-machining stainless steel with 85% machinability, the highest of all stainless steels. For most free-machining stainless steels, machinability can be improved by adding sulfur, which leads to the formation of manganese sulfide inclusions. Sulfur additions also reduce the formability, weldability, and corrosion resistance of 416 steel to levels below 410 grades. Because of its high machinability and low cost, Grade 416 steel is available in highly tempered, hardened, or unhardened form.

The manufacturing method of high hardness martensitic steel requires final quenching and tempering treatment. These steels have lower corrosion resistance than austenitic steels. The decrease in ductility of martensitic steel at sub-zero temperature and the decrease in strength due to excessive tempering at high temperature are two key factors affecting its working temperature.

Chemical composition of 416 stainless steel

material

416

chemical composition

ハ

マン

シ

P

s

クロム

モー

≦0.15

≦1.25

≦1.00

≦0.06

≧0.15

12-14

≦0.6

Mechanical properties of 416 stainless steel

material

416

mechanical properties

引張強度（MPa）

降伏強さ
0.2% Proof (MPa)

伸長
(% in 50mm)

Hardness Brinell
(HB)

517

275

30

262

Physical properties of 416 stainless steel

material

416

Physical Properties

 

密度 (kg/m3)

弾性率 (GPa)

Mean Coefficient of Thermal Expansion
(μm/m/°C)

熱伝導率
(W/m.K)

Specific Heat 0-100°C
(J/kg.K)

Electrical Resistivity (nΩ.m)

0-100°C

0-315°C

0-538°C

at 100°C

at 500°C

7800

200

9.9

11

11.5

24.9

28.7

460

570

Corrosion resistance of 416 stainless steel

Grade 416 steel is highly resistant to acids, alkalis, fresh water and dry air. However, their corrosion resistance is lower than non-machining steels, austenitic steels and 17% chromium grade 430 ferritic alloys. These steels are hardened for maximum corrosion resistance and a smooth finish. 416 easy-to-machine grade with high sulfur content is not suitable for chloride and marine environments.

416 stainless steel is a kind of stainless steel containing sulfur element, which has good corrosion resistance.

416 stainless steel has good corrosion resistance in the atmosphere, fresh water and many acid environments. It is resistant to common organic acids such as acetic and lactic acids, and also has good corrosion resistance to many inorganic acids such as sulfuric, phosphoric and hydrochloric.

However, 416 stainless steel has poor corrosion resistance in salt water and chloride environments containing chloride ions. In these environments, it is prone to pitting and intergranular corrosion problems. Therefore, in an environment containing chloride ions, other more corrosion-resistant stainless steel materials should be selected.

Generally speaking, 416 stainless steel has good corrosion resistance, but it needs to pay attention to its corrosion problem in some specific environments, especially the environment containing chloride ions. In the application, it is necessary to select the appropriate material according to the specific situation to ensure the corrosion performance requirements.

Heat resistance of 416 stainless steel

The scale resistance of Grade 416 steel is extended to 760°C under batch conditions and up to 675°C under continuous operation. Considering the sustainability of mechanical properties, the service temperature of 416 steel should not be higher than the standard tempering temperature.

416 stainless steel has certain heat resistance in high temperature environment.

The heat resistance of 416 stainless steel depends on the temperature range used. In ordinary air, the heat resistance of 416 stainless steel can reach 540°C (1000°F). At this temperature, it can still maintain good mechanical properties and corrosion resistance.

However, when the temperature exceeds 540°C (1000°F), the heat resistance of 416 stainless steel will decrease. At higher temperatures, 416 stainless steel may undergo thermal creep and oxidation, resulting in a decrease in the strength and corrosion resistance of the material. Therefore, in high-temperature environments exceeding 540°C (1000°F), other more suitable high-temperature alloys or stainless steel materials should be selected.

In general, 416 stainless steel has certain heat resistance and performs well in general high temperature environments. But in high temperature environments over 540°C (1000°F), other more heat-resistant materials should be selected to meet the needs. In the application, it is necessary to select the appropriate material according to the specific temperature requirements.

Heat Treatment of 416 Stainless Steel

416 stainless steel can change its structure and properties through heat treatment.

Commonly used heat treatment methods include annealing, solution treatment and quenching.

Annealing Treatment: Fully Annealed – Grade 416 steel can be annealed at 815 to 900°C for ½ hour. This process is followed by cooling for one hour at 30 °C and air cooling. Subcritical Annealing – heating grade 416 steel to 650 to 760°C and air cooling

Solution treatment: Solution treatment can dissolve the sulfide in 416 stainless steel, thereby improving its corrosion resistance. Solution treatment is usually carried out at a temperature of 980-1050°C (1795-1920°F), with a holding time of 1-2 hours, followed by rapid cooling. This process increases the hardness, strength and corrosion resistance of the material.

Quenching treatment: Quenching treatment can further increase the hardness and strength of 416 stainless steel, but it has a certain negative impact on corrosion resistance. Quenching is usually carried out at a temperature of 950-1070°C (1740-1960°F), followed by rapid cooling. Quenching can bring the material to the highest hardness and strength levels, but may lead to increased brittleness and the risk of intergranular corrosion.

Welding of 416 stainless steel

416 steel has poor weldability. Welding can be performed by preheating 416 steel to 200 to 300°C, followed by rehardening, annealing or stress relieving at 650 to 675°C.

416 does not have excellent welding properties and can be welded by preheating it to 200 to 300°C and then rehardening, annealing or stress relieving at 650 to 675°C.

Processing of 416 stainless steel

Grade 416 steel has the highest machinability of all stainless steels when subcritically annealed.

416 stainless steel has moderate machinability and can perform a variety of common metalworking operations. The following are some common 416 stainless steel processing methods:

Drilling and milling: 416 stainless steel can be processed into the desired shape and size by drilling and milling. Use proper tools and coolants to reduce cutting temperatures.

Cutting and cutting: 416 stainless steel can be cut using shears, clippers, or hand cutters. Pay attention to the selection of appropriate cutting tools and processing parameters to obtain a smooth cutting edge.

Bending and forming: 416 stainless steel can be bent into desired shape by mechanical bending or heat treatment. Pay attention to control the bending radius and temperature to avoid damage to the properties of the material.

Welding: 416 stainless steel can be welded by TIG welding, MIG welding or manual arc welding. Pay attention to the selection of appropriate welding parameters and filler materials to ensure the quality and performance of the weld.

Surface treatment: 416 stainless steel can be subjected to various surface treatments, such as polishing, sandblasting and electroplating, to improve appearance and corrosion resistance.

Application of 416 stainless steel

416 stainless steel is widely used in many different fields due to its good corrosion resistance, easy processing and mechanical properties.

The following are some common application areas of 416 stainless steel:

Knives and knife manufacturing: 416 stainless steel has good cutting performance and grinding performance, and is often used in the manufacture of various knives, such as blades, tool holders and cutter heads.

Valves and pumps: 416 stainless steel has good corrosion resistance and is often used to manufacture valves and pumps, valve bodies, pistons and other components.

Food processing equipment: 416 stainless steel has good corrosion resistance to food and beverages, and is widely used in food processing equipment, such as food cutting machines, food conveyor belts, and food packaging machines.

Medical devices: 416 stainless steel has good corrosion resistance to blood and body fluids, and is often used in the manufacture of medical devices, such as surgical instruments, dental instruments, and surgical implants.

Petroleum and chemical equipment: 416 stainless steel has good corrosion resistance in acidic and alkaline environments, and is widely used in the manufacture of petroleum and chemical equipment, such as oil drill pipes, storage tanks and pipelines.

Mechanical parts and connectors: 416 stainless steel has high strength and hardness, and is often used in the manufacture of mechanical parts and connectors, such as shafts, splines and bolts.

It is necessary to select appropriate 416 stainless steel materials and processing methods according to specific application requirements and environmental requirements to ensure its performance and service life.