How surface tension is measured for molten metals?

In summary, there are multiple methods for measuring the surface tension of molten metals and reactive substances, including the pendant-drop approach, maximum bubble pressure method, electrostatic levitation, and characterization of oscillating droplets. However, the most commonly used method for Earth-based measurements is the sessile drop, which involves calculating the best fitting mathematical shape of the drop. While some may consider this method inaccurate, a study from 1966 reported an acceptable level of precision in the results.
  • #1
ORF
170
18
Hello

How the surface tension is measured for molten metals? I have heard about the sessile drop, but it seems to be a very inaccurate method...

Thank you for your time.

Regards.
 
Engineering news on Phys.org
  • #2
Experimentalists have also looked at the size of a drop as it falls (e.g., the pendant-drop approach, J Tille and J C Kelly 1963 Br. J. Appl. Phys. 14 717), the maximum bubble pressure method, electrostatic levitation of oscillating droplets, and characterization of oscillating droplets in microgravity (I Egry, G Lohoefer, and G Jacobs 1995 Phys. Rev. Lett. 75, 4043). The penultimate method seems to be the consensus for Earth-based characterization of the surface tension of molten metals and strongly reactive substances. The final method provides a check against the methods used to correct for the influence of the strong EM field required for levitation.
 
  • #3
ORF said:
I have heard about the sessile drop, but it seems to be a very inaccurate method...
Hi ORF:

A long time ago I was involved in helping a physical chemist friend determine surface tension of mercury drops by developing a method of calculating the best fitting mathematical shape of a sessile drop to a set of observed shape measurements. As I remember, the paper that resulted reported an acceptable level of precision in he results.
"A curve fitting method for calculating interfacial tension from the shape of a sessile drop" James N. Butler and Burton H. Bloom, Surface Science 4 (1966) 1-17.​

Why do you think this method is inaccurate?

Regards,
Buzz
 

1. What is surface tension?

Surface tension is a physical property of liquids that measures the force required to break or deform the surface of a liquid. It is the result of the cohesive forces between molecules at the surface of a liquid.

2. How is surface tension measured?

Surface tension can be measured using various methods, including the pendant drop method, the capillary rise method, and the Wilhelmy plate method. Each method involves measuring the force required to deform the surface of a liquid, which is then used to calculate the surface tension.

3. Can surface tension be measured for molten metals?

Yes, surface tension can be measured for molten metals. However, the methods used for liquid surface tension measurement cannot be directly applied to molten metals due to their high temperature and reactivity. Therefore, specialized techniques, such as the sessile drop method, are used for measuring surface tension of molten metals.

4. Why is measuring surface tension of molten metals important?

Measuring the surface tension of molten metals is important for understanding their properties and behavior, which can have significant implications in various industrial processes such as metal casting, welding, and alloy production. It can also provide insights into the structure and composition of molten metals.

5. What factors can affect the surface tension of molten metals?

The surface tension of molten metals can be affected by factors such as temperature, chemical composition, and impurities. High temperatures can decrease surface tension, while certain elements or impurities can increase or decrease it depending on their interaction with the molten metal. The type of measurement technique used can also affect the surface tension results.

Similar threads

  • Materials and Chemical Engineering
Replies
12
Views
2K
  • Materials and Chemical Engineering
Replies
1
Views
1K
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
12
Views
856
  • Materials and Chemical Engineering
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
703
Replies
1
Views
406
  • Materials and Chemical Engineering
Replies
5
Views
2K
  • Classical Physics
Replies
23
Views
1K
  • Materials and Chemical Engineering
Replies
19
Views
3K
Back
Top