Stainless steel is not unfamiliar to each of us, and even stainless steel is used in many entrance tableware. When it comes to tableware, we are most concerned about health issues - the most basic requirement of tableware is that it cannot be corroded by food, otherwise it will cause harm to human health.
Friends who have purchased stainless steel tableware will find that there are four common stainless steel tableware - 304, 304L, 316 and 316L. What exactly do these four stainless steels mean? Which tableware is better?
What is stainless steel
The stainless steel we talk about every day does not just refer to "steel that does not rust". Its full name is called "stainless acid-resistant steel", which not only does not rust, but also resists acid corrosion. According to the ability of acid corrosion resistance, there are many grades. The four we are going to talk about today are part of the many grades.
The so-called 304 or 316 are all American ASTM standard grades. Of course, they all have corresponding national brand names, but why don't we say the national standard brand name? Because the national label is too complicated, taking 304 stainless steel as an example, the national label is called "06Cr19Ni10".
304 stainless steel and 316 stainless steel
We have a national standard for stainless steel tableware, called "National Standard of the People's Republic of China / Hygienic Standard for Stainless Steel Tableware Containers" (GB4806.9-2016). It specifies what kind of corrosion resistance standard stainless steel used in contact with food needs to meet.
There is no stainless steel grade directly in the national standard, but various types of stainless steel are tested according to the standard, and it is found that 304 stainless steel is the lowest grade that meets the standard - some businesses say that "304 stainless steel is food grade stainless steel" is actually inaccurate, There are many kinds of stainless steel "grade", 304 stainless steel is the minimum standard.
The common food in life basically cannot cause damage to 304 stainless steel. Naturally, there is no need to worry that the food will corrode the stainless steel and produce substances that are harmful to the human body, or eat it directly into the stomach.
But in the face of some special foods, such as carbonated drinks, milk, coffee, etc., 304 stainless steel is relatively weak. At this time, we need stainless steel with stronger corrosion resistance - 316 stainless steel is a product with slightly higher corrosion resistance than 304 stainless steel. It has enough corrosion resistance without increasing the cost too much, so it is also widely used in tableware. .
There are many stainless steels with stronger corrosion resistance than 316 stainless steel, but the cost increases too much, and the super corrosion resistance cannot be reflected, so it is rarely seen on tableware.