This presentation is about Beryllium, its chemical properties, physical properties and machining it.And twinning phenomenen

1. Theory of Metal Cutting
M1371
Dr. Ashraf Hassan

2. number
section
department
Student
10
1
production
Salma Mohamed Elnashar
13
1
production
Abdullah Mohamed Taha
14
1
production
Fady Essam Ali
19
1
production
Mahmoud Gamil Ahmed

3. 2.Machining Beryllium

4. Atomic
Number
Electronic
Configuration
Symbol
Atomic
Weight
Name

5. Beryllium
in Periodic table

6. Electronic Configuration [He] 2s2
Atomic Number 4
Atomic Weight 9.012 atomic mass units
Group, Period, and Block 2 (Alkaline Earth Metals), 2, s-block
Empirical Atomic Radius 105 pm
Covalent radius 96 ± 3 pm
Van der Waals radius 153 pm
Electrons: 4
Protons: 4
Neutrons in the most abundant
isotope:
5
Electron shells 2
,
2
Elemental properties

7. Physical properties
•Be is a light, silver-gray metal that is comparatively soft and robust
but brittle.
•Be has the greatest melting point of the light metals,
melting at 1278 °C – far higher than Lithium (180°C), Sodium
(98 °C), or Calcium (839 °C).
•Under normal circumstances, a thin layer of the hard oxide BeO
forms on the surface of Be, protecting it from further attack by water
or air.
•Be does not oxidize in air, even at 600°C
as a result of this BeO layer, and it is resistant to corrosion by
strong nitric acid.
•Be is also nonmagnetic and has a high thermal conductivity.
•It is found in 30 distinct minerals, the most notable of which are
bertrandite, phenakite, and beryl.
•Be content in the soil can be absorbed by plants if it is soluble.

8. Melting Point 1287°C, 2349°F, 1560 K
Boiling Point 2468°C, 4474°F, 2741 K
Density 1.85 g.cm-3
Critical Temperature 5205 K
Heat of Fusion 12.2 kJ/mol
Heat of Vaporization 292 kJ/mol
Molar Heat Capacity 16.443 J/(mol·K)
Electronegativity Pauling scale: 1.57
Physical properties

9. Chemical properties
•Be produces hydrogen gas when it reacts with certain acids or with
water.
•Be interacts with oxygen to generate BeO (beryllium oxide) when
exposed to air, but it resists oxidation at a specific standard pressure
and temperature.
•Be chemical behavior is mostly determined by its tiny atomic and ionic
radii.
When connected to other atoms, it possesses very high
ionization potentials and strong polarization, which is why all of its
compounds are covalent. Its chemistry is comparable to that of
aluminum, demonstrating a diagonal relationship.
•It dissolves well in non-oxidizing acids like HCl and dilute H2SO4, but
not in nitric acid or water because it creates oxide.
This is analogous to the behavior of aluminum metal. Be dissolves in
alkali solutions as well.
2+

10. Material property comparison

11. Machining of Beryllium
Machining beryllium
produces discontinuous chips, much like cast iron.
Because of the high value of clean dry chips that are not
contaminated by other metals, beryllium frequently is machined dry
during heavy stock-removal operations.
However, Brush Wellman has developed procedures to clean and dry
beryllium chips economically, and those procedures increasingly
allow machining with coolants.
Machining operations performed under a liquid coolant flood reduce
airborne-particle dispersion.
Coolants are used for deep-hole drilling and threading and finishing
operations in which close tolerances, long tool life and damage-free
surfaces are required. However, sulfurized and chlorinated grades of
soluble oils in coolants corrode or discolor the work material

12. Factors
we should care about during Beryllium Machining

13. Beryllium is abrasive and hard on tools.
High-quality carbide tools are required to machine this material.
Cutter life is about 10 percent that when cutting 6061 aluminum.
Tools must be kept sharp because dull tools create surface stresses and
cracking that makes it difficult to maintain tolerance.
Tool coatings are usually of little benefit because they rub off due to the
abrasiveness of beryllium.
Beryllium is machined by all common metalworking processes; however, tapping can be
difficult because of the high surface stresses involved and the lack of ductility of the
material.
If the machinability factor of free-machining steel is rated at 100 percent, the machinability
factor or beryllium is 55 percent.
Using the same comparison, titanium and its alloys range from 18 to 38 percent and
aluminum and brass are 120 to 200 percent.
Grinding is not generally used to remove large amounts of beryllium, and usually is reserved
for close-tolerance work and to produce fine surface finishes

14. Cutting beryllium produces surface microcracks, called twinning,
which extend to about 10 percent of the depth of cut.
Surface damage can be prevented by proper machining
procedures followed by stress relief heat treatment or chemical
etching to remove damaged surfaces.
Twinning

15. Because beryllium is brittle, extremely notch sensitive and can
be damaged easily by improper handling, tooling fixtures and
accessories must minimize bending forces and resultant
deflections or vibrations from tool pressures.
So,
Soft-jawed chucks with large contact areas are best.

16. “A general rule-of-thumb is that acceptable tolerances on all aspects of
processing pure beryllium are about half those required with other
materials,”
Greg Westbrook, engineering manager at LA Gauge Co. Sun
Valley, Calif., a fabricator of beryllium components.

17. Uses of Beryllium
•Be is alloying agent.
•Be has a wide temperature range thermal stability, high strength, non-magnetic
characteristics, and improved resistance.
•Be is commonly used in the defense and aerospace industries when fused with copper to
make alloys.
•Because Be is almost transparent to x-rays, unlike most metals, it is utilized in the radiation
windows for x-ray tubes.
•Using copper or nickel, Be metal is alloyed to create springs, spot-welding electrodes,
gyroscopes, and non-sparking tools
•Be is utilized in nuclear operations and is also thought to have ceramic applications due to
its high melting point.
•Moreover, they are dimensionally stable and exhibit non-magnetic characteristics throughout
a wide temperature range, making them a good metal for alloys. For instance, Beralcast is
an alloy made of Be and aluminum.
•Microwave ovens, high-speed computers, lasers, and other devices all employ Be
compounds.
•Be is also employed in nuclear reactors as a shield, moderator, and neutron reflector and
absorber.

18. • https://thechemistrynotes.com/beryllium-history-properties-important-
uses/#elemental-properties
• https://youtu.be/qy8JyQShZRA?si=Gr3U3WVi7ozrDG49
References

19. This presentation’s made by Salma Elnashar
for more:
Salm.elnashar@gmail.com
https://www.linkedin.com/in/salma-elnashar-
b75a90240?utm_source=share&utm_campaign=share_via&utm_
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Thank you
for your time and consideration