Can a disposable vape be detected in a metal detector?

Yes, disposable electronic cigarettes are usually detected by metal detectors. However, whether an alarm will be triggered mainly depends on the sensitivity of the detector.
?? Why was it detected?
Even though the outer shell of your disposable e-cigarette is made of plastic, the core components inside are all made of metal:
Lithium-ion battery: This is the most crucial metal component, containing copper, aluminum, lithium, etc.
Heating coil: Usually made of nickel-chromium alloy or stainless steel, it is used to heat the e-liquid.
Internal circuit board: It contains various metals such as copper, silver and tin.
An analysis study of nine popular disposable electronic cigarettes revealed that the metal content in these devices can reach up to 85% of their dry weight. Therefore, even if the outer casing is made of plastic, there is still a considerable amount of metal inside.
?? Under what circumstances will an alarm be triggered?
This mainly depends on the sensitivity setting of the detector:
High-sensitivity areas (such as airports, government buildings): The detectors here are set to a very high sensitivity level, aiming to catch any suspicious items. In such circumstances, a disposable electronic cigarette would almost certainly trigger an alarm.
In general, in sensitive areas (such as concerts, stadiums, courts): To speed up the entry process, the detectors in these places may have a lower sensitivity, mainly targeting large metal items like knives and guns. Your e-cigarette might be overlooked. Some security personnel carrying detectors have extremely high sensitivity, capable of detecting 1-centimeter-long iron wires, and it's basically impossible to evade detection.
Low-sensitivity areas (such as Disneyland): The security checks in these areas do not focus on e-cigarettes, so they usually do not trigger alarms.
?? What should you do when going through security checks?
To avoid any trouble for yourself, here are two most practical suggestions:
Take it out voluntarily: The easiest way is to act like you do with your phone or keys, and voluntarily remove the e-cigarette from your pocket before going through the security check, and place it in the security basket. This can prevent being stopped for a more time-consuming individual inspection due to the alarm sound.
Comply with aviation regulations: If flying by plane, electronic cigarettes must be carried with you (in your carry-on bag) and must not be checked in. This is to prevent any accidents involving lithium batteries in the cargo hold.
Overall, in places like airports where security checks are strict, one should not take any chances. The simplest and safest way is to put the e-cigarette in your bag and go through the X-ray machine.