304 stainless steel rods are: stainless steel hexagonal rods, stainless steel square steel, stainless steel polish rods, grinding stainless steel bar, stainless steel bright bar, import stainless steel rods, the domestic stainless steel rods, stainless steel easy car, SUS303 bar, SUS416 bar, our products are good cutting performance and drilling performance, stable size precision, finish good, free cutting processing various parts with high precision.
Mirach Stainless steel mill specialized in stainless steel production and trade enterprises. Over the years has been committed to the promotion and sales of stainless steel products, the main 304 stainless steel rods, 321 stainless steel rods, 316 l stainless steel rods, 310 s stainless steel rods, 304 stainless steel round steel, 321 stainless steel round steel, 316 l stainless steel round bar, 310 s stainless steel round steel and other products.
Now a lot of industrial products, can use stainless steel material to make, in order to identify stainless and inferior, can take some measures and methods. But many do not know with what method can discriminate, out of the following four chemical identification methods of stainless steel bars.
A magnetic test method, magnetic test method – is the most primitive one of the most common difference between austenitic stainless steel and ferritic stainless steel of the most simple way to austenitic stainless steel, nonmagnetic steel but after cold work under big pressure to have mild magnetic; And pure chromium steel and low alloy steel are strong magnetic steel.
Second point, nitric acid test of stainless steel is a striking feature of nitric acid and dilute nitric acid have inherent corrosion resistance, this performance make it can easily distinguish from most other metals or alloys. But high carbon type 420 and 440 steel in nitric acid test is a little corrosion, when meet with nitric acid was immediately non-ferrous metal corrosion, dilute nitric acid on carbon steel has strong corrosive.
, law – copper sulfate point try to be quick to distinguish between ordinary carbon steel and the easiest way of all types of stainless steel, the use of the concentration of a solution of copper sulfate is 5% – 10%, before point tests, test area should be thoroughly remove oil and other impurities, cloth or soft grinding polishing and grinding machine small area, and then try the droplets to burnish, ordinary carbon steel or iron within a few seconds can form a layer of metal copper surface, and test the surface of the stainless steel is not produced copper precipitation or display the color of copper.
Four, sulfuric acid test – sulfuric acid immersion stainless steel can make a distinction between 302 and 304 and 304 and 316. Sample should pass fine grinding, cutting edges and the volume concentration of 20% ~ 20%, the temperature of 60 ~ 66 ℃ in sulphuric acid cleaning and passivation for half an hour, the volume concentration of the sulfuric acid solution was 10%, when heated to 71 ℃, 302 and 304 in solution in steel corrosion was quickly and produce a large number of bubbles, in some kind of black sample; While sample in 316 and 317 steel from corrosion or corrosion slow (not have bubbles), test does not change color within 10 ~ 15 minutes. If at the same time test specimen with a known component is used to compare similar words, can make the experiment more accurate.