How to identify 321 stainless steel? Come professionally

Those who understand stainless steel come in to help the materials of stainless steel pipes, what are the differences between them, how to distinguish their materials, how to distinguish the materials of 304 and 316, it is best to be detailed. In the small business, for material identification, use a portable grinder and angle grinder to make sparks, and judge the steel number according to the shape and color of the sparks, bifurcation and bursting characteristics; If you have a bad eye, you can use a digital camera to capture and freeze color images to analyze the spark pattern of steel under the friction of high-speed grinding wheels. To make a big deal, take samples, use portable grinders, angle grinders or hand saws, intercept samples, and go to non-ferrous metal research institutes, research institutes, scientific research institutes, colleges and universities to do spectral analysis, chemical titration and quantitative analysis.

In the vicinity of the stainless steel wholesale market, there are privately formulated reagents that can determine the nickel content. The large domestic stainless steel processing enterprises also adopted this method at the beginning, and now they have purchased traditional spectral analysis instruments to scientifically determine the content of various elements. In fact, metallographic analysis of steel can also get results quickly, requiring a good microscope and a few cheap metallographic sandpapers.

How to distinguish tempered glass from ordinary glass? Illuminate with polarized light, visually with polarized light lenses, pay attention to the mutual angles of the two polarizers, and use a polarized light filter. The LCD screen of electronic watches and calculators has two liquid crystal filters, which can be disassembled for use, and the computer LCD screen also has a large area of polarizers, so you can observe the interference effect formed by the pre-loading stress of the tempered glass.

It can also be observed with a metallographic microscope, where there is also polarized light. The basic preparation of the metallurgical microscope is 8,000 yuan, plus the camera and image card, it will cost 2,500 yuan a set. Good stainless steel, with a few hundred watts of angle grinder, it is best to use a large disc grinding wheel cutter to cut hard, so that the incision is red, after the incision is cooled, the material of the incision blackened may be stainless iron, which may have low nickel content, and the material with yellow incision has high nickel content, which is a simple qualitative comparison.

How to identify 321 stainless steel in this question? It's so hard to come to the major, it's hard work, give me a satisfactory answer.

There are no 18 nickel steel grades are 1cr18ni9ti nickel 7-9 titanium chromium 17-19 it is best to go to the steel research institute for testing There are also potions that you can order yourself.

The two stainless steels cannot be distinguished by the naked eye, and can be distinguished with potions. Connect the positive and negative stages of the battery to the line, drop the potion, put the positive level on the potion, and put the negative level on the metal, 304 is a normal red, 316 because it contains mo, so if you use the ni8 potion, it will generally turn black.

The main differences between 304 stainless steel and 316 stainless steel are:

1. The difference in the main components of the metal: 304 stainless steel and 316 stainless steel contain about 16 18% chromium, but 304 stainless steel contains 9% nickel on average, while 316 stainless steel contains 12% nickel on average. Nickel can improve high-temperature durability, improve mechanical properties, and improve oxidation resistance in metal materials.

Therefore, the nickel content of the material directly affects the comprehensive properties of the material.

2. The difference in material properties: 304 (0Cr18Ni9) stainless steel is austenitic stainless steel, which cannot be strengthened by heat treatment, cannot be quenched like carbon steel, and has no magnetism. The main characteristics of 316 are that the ability to resist acid and alkali and high temperature is stronger than that of 304, and it is mainly used in the food industry and surgical equipment, and there is basically no phenomenon of thermal expansion and cold contraction.

Hello, the difference between these two kinds of stainless steel: 1. The characteristics are different.

The performance of 304 processing is high and strong. 316 is corrosion-resistant, atmospheric and high-temperature.

2. The application field is different.

304 is widely used in industrial and home decoration industries, while 316 is generally used in seawater with equipment, chemicals, and dyes.

Oxalic acid, papermaking.

fertilizer and other production equipment and other industries. 3. The density is not the same.

The density of 304 is. The density of 316 is:

The difference between 304 and 316 stainless steel is introduced here, I hope it will help you.

1. Stainless steel 321 material is 0Cr18Ni10Ti.

Stainless steel is NI-CR-TI type austenitic stainless steel, which has abrasion resistance, high temperature resistance, creep resistance, etc., and is used to manufacture wear-resistant acid containers and linings for wear-resistant equipment, conveying pipelines.

Ti in stainless steel exists as a stabilizing element, but it is also a thermally strong steel grade, which is much better than 316L in terms of high temperatures. 321 stainless steel has good abrasion resistance in organic and inorganic acids at different concentrations and temperatures, especially in oxidizing media.

321 stainless steel is a titanium stable grade that is typically used in the temperature range of 538-870°C. For service temperatures up to approximately 870°C, it can be stabilized under air cooling at 842-899°C to provide optimal resistance to heat-affected zone (HAZ) intergranular corrosion.

and polysulfuric acid stress corrosion cracking ability.

Alloy 321 stainless steel can be welded by including submerged arc welding.

and all common methods of easy welding. A suitable weld filler is AWS ER347 bare wire and E347 clad electrode. Alloy 321 stainless steel has good machinability and is easy to manufacture.

Characteristic. Density: grams of cubic centimeters.

Melting range: 1400 1427 °C

Specification. UN ID: UNS Code: Standards: ASTM A240, A276, A312, A479, AMS

Alloy 321 can be used in a variety of applications, including:

Aircraft piston engine manifolds.

Expansion joints. Thermal oxidizers.

Oil refining equipment. High-temperature chemical process equipment.

There are 6 simple ways to detect whether 304 Sakurachai is.

1. Friction spark identification method: 304 material and 201 material are used respectively, and the sparks generated are placed on the high-speed rotating grinder to see the sparks, due to the effect of friction and high temperature, the number of sparks and the shape bifurcation of various Yuanwang Xiaolin particles are different to identify the chemical composition and approximate content of the material.

2. Stainless steel potion identification method: you can buy it directly from stainless steel accessories stores (such as Jiangtou Fansheng and Xin Yongsheng), with a unit price of 15 yuan a bottle. The stainless steel identification potion is dropped on the 304 material and 201 material respectively, and it can be distinguished in two to three minutes, and different colors will be displayed, and then refer to the manual for comparison.

3. Surface observation, first look at whether there is rust on the surface of the utensils, if there is no rust, it can be determined that it is stainless steel, but it cannot be concluded from this.

4. Potion testing, there are materials on the market to test water, after dripping, different colors correspond to different materials, which is very simple and convenient, and you can roughly judge which type of stainless steel material it is.

5. Grinding detection, grinding wheel grinding to see the state of the spark, but this method needs to be identified by experienced people.

6. Spectral detection, instrument identification is the safest and most difficult to contain accurate methods. First, the surface is beaten off with a grinder, but the surface must be smooth and then beaten with a spectrum, which can read the metal elements in the material in detail, and then compare the material, this method is the most reliable and authoritative.

Distinguish 316 stainless steel:

1. Distinguish between potions.

There are special tests for 304 stainless steel and 316 stainless steel potions on the market, if you want to judge whether your stainless steel is made of 316 material, you can buy 316 stainless steel potions to test.

Now the most commonly used two stainless steels 304,316 (or corresponding to the German and European standards,,The main difference between 316 and 304 in terms of chemical composition is that 316 contains MO,And it is generally recognized that 316 has better corrosion resistance,More corrosion resistance than 304 in high temperature environments。 Therefore, in a high-temperature environment, engineers generally choose parts made of 316 material.

2. Spectrometer detection.

The stainless steel detection spectrometer can detect the elemental content of stainless steel wires; As long as you test it, you can know whether it is 316 stainless steel wire.

3. Salt spray test to detect and distinguish.

The salt spray test time of 201 stainless steel is 24 hours; The salt spray test time of 304 stainless steel is 48 hours; The salt spray test time of 316 stainless steel is 72 hours.

First of all, it is impossible to tell with the naked eye whether it is 316 stainless steel or not.

A quick and easy way to identify the chemical composition of a material is with a handheld spectrometer.

Another is to use a potion to determine its nickel content to determine whether it is 316.

The accurate method is chemical composition analysis, which takes a long time.

You can learn about one way to quickly identify the chemical composition of a material with a handheld spectrometer.

1: Grade 316Ti stainless steel.

Two: chemical composition.

c：≤ si≤ mn≤ p≤ s≤ ni crmo ti≥5*c%~

Three: the scope of application, the field of application:

316L stainless steel is added with MO, so its corrosion resistance, atmospheric corrosion resistance and high temperature strength are particularly good, and can be used under harsh conditions; Excellent work hardening (non-magnetic). Excellent strength at high temperatures. 316L stainless steel is an austenitic stainless steel and cannot be strengthened by heat treatment.

It has good strength, plasticity, toughness and cold formability, as well as good low-temperature properties. Due to the addition of 2% MO on the basis of Cr18Ni8, the steel is endowed with good resistance to reducing media and pitting resistance. It has suitable corrosion resistance in various organic acids, inorganic acids, alkalis, salts and seawater.

In reducing acidic media, its corrosion resistance is much better than that of 304

Four: Overview. The corrosion resistance of stainless steel is better than that of 304 stainless steel, and it has good corrosion resistance in the production process of pulp and paper. And 316 stainless steel is also resistant to the erosion of the ocean and the aggressive industrial atmosphere. In intermittent use below 1600 degrees and continuous use below 1700 degrees, 316 stainless steel has good oxidation resistance.

In the range of 800-1575 degrees, it is better not to act continuously on 316 stainless steel, but when 316 stainless steel is used continuously outside of this temperature range, the stainless steel has good heat resistance. 316L stainless steel has better resistance to carbide precipitation than 316 stainless steel, and can be used in the above temperature ranges. Annealing is carried out in the temperature range of 1850-2050 degrees, followed by rapid annealing, followed by rapid cooling.

It is resistant to high temperatures, easy to process, and high strength. 316L stainless steel, no post-weld annealing is required.