Physical Property Measurements of Glassy Metals

1
Physical Property Measurements of Glassy Metals

• Michael Hall
• Six Month Intern
• Drexel University
• Measuring Thermal Properties

• Valerie Cervantes
• High School Student
• Mayfield Senior School
• Data Processing

2
The Quantum Design Cryostat

• Temperature Range 1.9K 400K
• Pressure 8.9 x 10-5 Torr
• Samples Metglas, MoRuB

3
Thermal Transport - Theory

• Generate Heat Pulse
• Measure ?T Thot - Tcold
• Estimate Corrections
• Calculate Thermal Conductivity!

4
Thermal Transport - Hardware
5
The Cryostat HiVac System

• HiVac Pressure 9x10-5 Torr
• Many Problems!!
• Result Quantum Design is Redesigning Cryopump

6
Cryopump Failure
7
Continuous Measurement
8
Ideal Data Acquisition
9
Poor Data Acquisition
10
TTO Stable Measurement
11
Data Processing
12
Data Processing
?T
13
Thermal Transport Formulas

• Conductance
• K P/?T
• Conductivity
• ? (PIN-PRAD)/?T-KWIRES(L/A)
• PRAD ??(S/2)(THOT4-TCOLD4)
• KWIRES is Measured Directly!

14
Measurement Adjustments

• Stable Measurements
• ?T 0.5K 1.5K
• Measure Parasitic Conductance
• Manual Data Processing

15
Thermal Conductivity
16
Heat Capacity - Theory

• Generate Heat Pulse
• Measure RC
• Estimate Corrections
• Calculate Heat Capacity!
• ?T T?exp-t/R8(CPCGCS)

17
Heat Capacity Sample Data
18
Q Factor Measurement