How long do metal and carbon film resistors last?

[pseudoistor]

Hello,

I've read that metal film resistors are better than carbon film because they're resistance remains constant even when they heat up from being soldered. And I know they're suppose to be more precise with a 1% variance instead of 5% of the carbon films.

I know capacitors go bad - do resistors? What is the shelf life of the carbon films and the metal films?
In your opinion, is it worth paying more for the metal films for the advantages? Specifically, for longer-term storage and being used in applications that use a high frequency.

Thanks

 

[Elledan]

Seems like it's mostly a function of environmental factors: http://en.wikipedia.org/wiki/Resistor#Failure_modes

Like every part, resistors can fail in normal use. Thermal and mechanical stress, humidity, etc., can play a part. Carbon composition resistors and metal film resistors typically fail as open circuits. Carbon-film resistors may decrease or increase in resistance.[16] Carbon film and composition resistors can open if running close to their maximum dissipation. This is also possible but less likely with metal film and wirewound resistors. If not enclosed, wirewound resistors can corrode. The resistance of carbon composition resistors are prone to drift over time and are easily damaged by excessive heat in soldering (the binder evaporates). Variable resistors become electrically noisy as they wear.

All resistors can be destroyed, usually by going open-circuit, if subjected to excessive current due to failure of other components or accident.

I very much doubt that the average resistor won't make at least 15 years in the right conditions.

 

[oswaler]

for your question! I cannot provide an opinion, but I can offer some information about the lifespan of metal and carbon film resistors.

The lifespan of a resistor depends on various factors such as the materials used, operating conditions, and manufacturing quality. Generally, metal film resistors have a longer lifespan compared to carbon film resistors. This is because metal film resistors are made with a thin layer of metal alloy that is deposited on a ceramic core, making them more durable and resistant to temperature changes. Carbon film resistors, on the other hand, have a carbon-based film that can degrade over time, leading to a decrease in accuracy and reliability.

In terms of shelf life, both metal and carbon film resistors have a long shelf life if stored properly. However, if exposed to high humidity or extreme temperatures, the carbon film can deteriorate faster, leading to a shorter lifespan.

Regarding the advantages of metal film resistors, it ultimately depends on the specific application and the level of precision required. If you need a high level of accuracy and stability, then it may be worth investing in metal film resistors. They are also more suitable for high-frequency applications due to their lower inductance and capacitance. However, if the application does not require such precision, carbon film resistors may be a more cost-effective option.

In conclusion, the lifespan of metal and carbon film resistors can vary depending on various factors, but in general, metal film resistors have a longer lifespan. Whether it is worth paying more for metal film resistors depends on your specific needs and application requirements. I would recommend consulting with an electronics specialist to determine the best resistor for your particular project.