Will Stainless Steel Jewelry Attract Metal Detectors? The answer is not absolute, metal detectors are difficult to detect 316 stainless steel jewelry, but 304 stainless steel jewelry generally attracts metal detectors, if you want to know why explore the mysteries with me now.
Definition and Classification of Metal Detectors
Simply put, a metal detector is an instrument used to detect the presence of metal nearby. It is mainly divided into three categories: electromagnetic induction, X-ray detection, and microwave detection.
Scope of application of metal detectors
In recent years, metal detectors have been widely used in military, archaeological, industrial, food and safety detection, and other fields. Based on different application environments, metal detectors usually have different metal detection requirements. Among them, the most well-known are hand-held metal detectors and metal security gates. They are usually found in high-traffic public places such as airports and stations. They have the characteristics of fast scanning speed, simple operation, and high sensitivity, so they are often used to detect whether there are weapons, explosives, and other dangerous objects in the human body or luggage. This ensures the safe entry and exit of personnel.
How Metal Detectors Work
1, The working principle of electromagnetic induction metal detector:
refers to the phenomenon of induced electromotive force due to the change of magnetic flux. The principle is that in the process of the magnet passing through the coil, the coil cuts off the magnetic field, thereby generating an induced current, and the pointer of the galvanometer is deflected.
2, The working principle of X-ray metal detectors:
X-ray detection refers to the use of X-rays to penetrate metal materials and convert the ray intensity distribution after passing through the metal materials into TV images.
3, The working principle of microwave metal detector:
Like radar, the scientific name of radar is “electromagnetic wave detector”. The radar emits intermittent electromagnetic waves, receives the returned electromagnetic waves, and the speed of the object can be calculated from the time difference to infer its distance.
Experimental detection of different metals by metal detectors
Sensitivity is an important indicator to judge the accuracy of metal detectors. The metal balls of iron, copper (non-ferrous metals) and 316 stainless steel pass through the center point of the opening of the metal detector respectively. The smaller the diameter of the metal ball, the higher the sensitivity.
96% of metal detectors use: a 25k Hz~1000k Hz electromagnetic wave transmitting source (middle coil) and electromagnetic wave receiving end (coils on both sides). When no object passes through, the two receiving coils get two different phase-fixed sine waves. Based on this, when iron, copper (non-ferrous metal), and 316 stainless steel pass through the metal detector, the magnetic field strength of the two sine waves is judged according to the degree of change in the phase difference of the two sine waves.
It can be simply understood that the more twisted the red line is and the closer it is to the small black dot in the middle, the stronger the magnetism of the metal.
In 1865 Maxwell’s equations revealed that a changing electric field produces a magnetic field, a changing magnetic field produces an electric field, and the changing electric and magnetic fields are always related to each other to form a unified electromagnetic field;
Electromagnetic waves are transverse waves, and the electric and magnetic fields that make up electromagnetic waves are 90 degrees out of phase. Different metal foreign objects have different electromagnetic induction under the action of the magnetic field and electric field of the metal detector. If we define magnetic field or permeability as the X coordinate, and electric field or conductivity as the R coordinate.
That is to say, iron has a strong magnetic field induction, that is, the magnetic permeability is very strong, close to the magnetic permeability coordinates, the original magnetic flux is enhanced, and the metal detector is easy to detect. 316 stainless steel is non-magnetic but has a certain degree of conductivity, so close to the conductive coordinates, the original magnetic flux is weakened, and it is difficult for metal detectors to detect.
Metal type Magnetic Conductivity Degree of detection Iron Yes Good Simple Stainless Steel (S304) Yes Bad General Copper (without iron) No Very good General Stainless Steel (S316) No Bad Bad
Degree of detection
Stainless Steel (S304)
Copper (without iron)
Stainless Steel (S316)
So if we wear jewelry made of 316-grade stainless steel, there will be no metal detectors. If you don’t want to waste too much time at security, try wearing 316-grade stainless steel jewelry. If you want to learn more about what 316L stainless steel jewelry is, you can check out our previous article: https://cfenjewelry.com/what-is-316l-stainless-steel-jewelry/
Now, let’s move on.
Will body-piercing jewelry trigger a metal detector?
If you have a body piercing and wear stainless steel (not grade 316) piercing jewelry, metal detectors are often difficult to detect due to their weak magnetism. However, airport security has three items, metal detectors, and X-ray scans. and manual inspection. So after passing the metal detector level, you have to accept the other two levels. In addition, the risk increases with excessive piercing and wearing of larger body accessories.
Of course, gold, sterling silver, and other jewelry trigger metal detectors, including our belt buckles, keys, and more.
So when we are ready to take off, we should pay attention to the following points:
1. Try to avoid wearing heavy jewelry. The larger the metal volume, the easier it is to cause the metal detector to alarm.
2. Package your jewelry individually. On the one hand, it helps to organize luggage and save space. On the other hand, if the metal detector detects it, it can be taken out in time for security inspection, so that it can be released.
3. Take off your jewelry. Such as rings, earrings, necklaces, bracelets, etc., take them off directly, put them on the tray provided by the staff, and put them on after security check.
Do body implants trigger metal detectors?
Seeing this, you may also wonder, will metal implants in the body trigger metal detectors after surgery? It depends on the actual situation. If it’s cobalt-chromium, yes, if it’s stainless steel or titanium, no. Titanium is generally considered a non-magnetic metal because of its weak magnetism. In this case, it is best to inform security personnel in advance of your medical condition and provide relevant proof or be screened by them.
Generally speaking, metal detectors are not sensitive to stainless steel jewelry, and grade 316 stainless steel is not magnetic, but has poor conductivity, making it difficult for metal detectors to catch. Grade 304 stainless steel is magnetic but less conductive, and with no accident, it will trigger a metal detector.
Now that you know what stainless steel jewelry won’t attract metal detectors, it’s time to start looking. There are plenty of places to buy something cute, fun, or sophisticated. However, make sure you do your research first.
Chengfen jewelry is a company specializing in the production and sales of 304, 316l stainless steel jewelry, we provide OEM and ODM services.