How is outgassing measured?
The outgassing rate is measured in quantity of gas (pressure x volume) per unit surface area per unit time. Knowledge of the outgassing rate is required to relate the ultimate pressure that will be achieved in a chamber to the pumping speed.
What is an example of outgassing?
The release of gases during volcanic eruptions is one example of outgassing; releases at submarine hydrothermal vents are another.
What is the definition outgassing?
transitive verb. 1 : to remove occluded gases from usually by heating broadly : to remove gases from. 2 : to remove (gases) from a material or a space. intransitive verb. : to lose gases.
What happens during outgassing?
Outgassing is the process in which a non-metallic material such as a polymer, adhesive, rubber, or potting compound / epoxy will release a gas when exposed to heat and or a vacuum. This gas will eventually condense on other materials, and could render them inoperable.
What material is an Outga?
The most predominant gases / vapors outgassing from surfaces are water vapor, oil and grease vapor, solvents, organic materials. In the upper reaches of Ultrahigh (UHV) vacuum, the stainless steel used to manufacture much of the chamber itself outgases hydrogen and carbon monoxide to some degree.
Do all plastics outgas?
Different plastics have different outgassing performance. PVC’s, for example, tend to be poor performers with high outgassing properties, while Fluoropolymers (PEEK, PTFE, etc.) tend to be the best plastics for low outgassing.
What is considered low outgassing?
To meet NASA Outgassing requirements, TML must be less than 1% and the CVCM must be less than 0.1%. Both requirements must be met to be considered a NASA Low Outgassing material. Most recently, EB-135 was tested for NASA Outgassing and passed at 3 different cure schedules.
What happens after outgassing?
The effects of outgassing can impact a wide range of application areas in electronics, from satellites and space-based equipment to medical systems and equipment. In space-based equipment, released gas can condense on such materials as camera lenses, rendering them inoperative.
How do you speed up outgassing?
How to speed up off gassing
- Ventilate, either with your HVAC system or by opening the windows, by using fans etc.
- Heat. As offgassing rate rises with temperature, a heater may be useful.
- Let a new product air out before using it. This one is not easy, especially for a couch or a mattress.
Is PTFE low outgassing?
Another – polytetrafluoroethylene (PTFE) – is a synthetic fluoropolymer that is commonly used inside of vacuum systems. It, too, has low outgassing and is self-lubricating, a good electrical insulator, and tolerant to fairly high temperatures.
What material is outgas?
What is RML in outgassing?
RML (Recovered Mass Loss): Mass loss after water absorption during post-conditioning (relative to initial sample mass)
What are the steps to the outgassing test?
The steps to this test include: The weight of the sample is taken before and after the experiment and the materials are considered to have passed if the total mass lost (TML) and the collected volatile condensible materials (CVCM) are below 1.0% and 0.10% respectively.
What is the definition of the outgassing rate?
Outgassing is described in terms of the rate of desorption of gas from a vacuum surface. The measured (or net) outgassing rate is the difference between the intrinsic outgassing rate (of the component) and the rate of re-adsorption on the surfaces of the test chamber [1]. The specific outgassing rate defined as
How is outgassing measured in a thermal test?
(see Advanced Outgassing ). The samples are submitted to pre-conditioning (24 hours at 22°C and 55%rH) to allow moisture uptake. During the thermal test (125°C for 24 hours) the outgassing behaviour is assessed by measuring the weight of the samples before and after thermal treatment.
Is it possible to test mirrors after outgassing?
Thus, it is possible to evaluate the possible contamination of sensible components (such as mirrors) by outgassed material. As for many applications the water-loss is not relevant, samples are also weighted after a post-conditioning (24 hours at 22°C and 55%rH) allowing recovery of lost moisture.