New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here


by: Mrs. Linda Wiegand


Mrs. Linda Wiegand
GPA 3.69


Almost Ready


These notes were just uploaded, and will be ready to view shortly.

Purchase these notes here, or revisit this page.

Either way, we'll remind you when they're ready :)

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

Class Notes
25 ?




Popular in Course

Popular in Physics 2

This 5 page Class Notes was uploaded by Mrs. Linda Wiegand on Friday September 18, 2015. The Class Notes belongs to PHY 4550 at University of Florida taught by Staff in Fall. Since its upload, it has received 6 views. For similar materials see /class/206780/phy-4550-university-of-florida in Physics 2 at University of Florida.


Reviews for CRYOGENICS


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 09/18/15
Properties of Materials at Low Temperatures J G We Srmrtorrl Linanr Acaclemmr Cciilcl Introduction Many materials are unsuitable for low temperature use Material selection must always be done carefully A signi cant amount of material data at low temperatures is avai a e u Testing may be required Some Unsuitable Materials for Low Temperature Use a see sea V77a iee rt Manensitic stainless steels Undergoes ductile to brittle transition wlien cooled dow I l Carbon steels also becomes brittle Rubber Teflon and most plastics 77v hv fi Oigtiiwik Introduction Ase awkaewes Weigh a Material properties change sign antly with em cralurc 0 quot55 r 2 elhe variaii n orerrorm a simple average between known values a Kelvin K c 273 Cryogenics is generally de ned as lt lzo K Some Suitable Materials for ow Temperature Use b aeieiew Thermal Contraction a Large amounts ol39contractiaii can occur when materials are cooled to cryogenic temperatures onevclopment of interferences or gaps duc to dissimilar materials Olnci39eased strain and possible failure olmpnet on wiring OMost contraction occurs above 77 K mm 20m ra Warsml Why does fiber glass not shrink as much as a pure plastic on cooHng Integral w Thermal Contraction A It has no plastic in it B Glass shrinks very lime C It is m gic w Strength Of Materials a 77v ki v if a Tends to increase at low temperatures as long as there is no ductile to brittle transition 300 K values are more conservative 1 Slight improvement in fatigue properties at cryogenic temperatures Speci c Heat of Solids C QInAT 39139f In general at cryogenic temperatures C 5 decreases rapidly with decreasing temperature This has 2 important effects oSystems cool down faster as they get colder oAt cryogenic temperatures small heat leaks may cause large temperature rises Thermal Conductivity vrv v geist k Varies signi cantly with temperature Temperature dependence must be considered when calculating heat transfer rates mm m n s m u Heat Flow Fatalquot IMF Temperature um area grm 39mr Harm er 7 LEE MA 4 Ax T em condnnivigv Thermal Conductivity Mean Mrlirrlt39 anfm l 1 pm Penicil r uni I39ld it vul ill v deimn n Cu 3 cvdquot mgmm 39 a 1mm Ni 7 Amsmfr 39J rerdupl irily umber Thermal Conductivity 7 Solutioanse thermal cnnduclh nlegrais Conduction heat transfer may be written as Q G92 e where the geometry Factor G is de ned by w Thermal Conductivity 777477V4770 g 7777 7 The them39lal conductivity integrals are then e med as Ti 9 i l K T IT Advantages 0 Simple a Only end point temperatures are important The actual temperature distribution is not a 5 Wm wt 20 m Electrical Resistivity i i iva k Drups with temperature due tn reduc phonon electran scattering RRR resistivity at 300 K resistivity at 42 K An indication of material purity Superconductivity a separate course Me mini mi in39 Electrical Resistivity of Copper 5 Wm i Ebc onsasaldealGas w nmu C omiuwivixiay or quotv M and c my A n10quot T termini Electriml W b t i u l i m z 4k T Islinhet aimm39tlpe 511 0 E23 Wh cmmmilx mnzmw a mva m i WedemannanzLorentz Law ir menmi camim39vity r Seatnualnmducliv y L Lurenz rumba With quantum treatment a 245 x ID SWQ 1K1 Real values


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Jennifer McGill UCSF Med School

"Selling my MCAT study guides and notes has been a great source of side revenue while I'm in school. Some months I'm making over $500! Plus, it makes me happy knowing that I'm helping future med students with their MCAT."

Bentley McCaw University of Florida

"I was shooting for a perfect 4.0 GPA this semester. Having StudySoup as a study aid was critical to helping me achieve my goal...and I nailed it!"


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.