airbuske
Posts: 194
Joined: Tue Jun 19, 2007 9:36 am

TiGr Vs Glare

Fri Apr 11, 2008 5:29 am

The demands for both military and commercial aircraft to fly faster and longer than ever before have led to the rapid advancement of structural materials. The industry requires these materials to exhibit improved damage tolerance and strength at extreme temperatures, improved resistance to corrosion and an increased fatigue life.

Airbus chose GLARE for the A380 program and Boeing has gone with TiGr for the 787 program. I know that GLARE is Al/Glass fibre while TiGr is Titanium/Graphite fibre, but what are the pros and cons of the two? What other composite laminates are widely used in the aerospace industry?
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: TiGr Vs Glare

Sat Apr 12, 2008 12:40 am



Quoting Airbuske (Thread starter):
Airbus chose GLARE for the A380 program and Boeing has gone with TiGr for the 787 program. I know that GLARE is Al/Glass fibre while TiGr is Titanium/Graphite fibre, but what are the pros and cons of the two? What other composite laminates are widely used in the aerospace industry?

Well, I know next to nothing about TiGr but, based just on what you've said, it's going to be a lot more expensive and heat tolerant than GLARE. With composites all things are variable, but the on-axis modulus of TiGr is going to be higher than GLARE for similar construction (fiber and metal fractions).

Tom.
 
airbuske
Posts: 194
Joined: Tue Jun 19, 2007 9:36 am

RE: TiGr Vs Glare

Mon Apr 14, 2008 9:28 pm



Quoting Tdscanuck (Reply 1):
but the on-axis modulus of TiGr is going to be higher than GLARE for similar construction (fiber and metal fractions)

What do you mean buy on-axis modulus?
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: TiGr Vs Glare

Tue Apr 15, 2008 12:42 am



Quoting Airbuske (Reply 2):
Quoting Tdscanuck (Reply 1):
but the on-axis modulus of TiGr is going to be higher than GLARE for similar construction (fiber and metal fractions)

What do you mean buy on-axis modulus?

Fiber reinforced composites are highly anisotropic (their material properties vary depending on what direction you test them). "On-axis" means in line with the fibers. The primarily load carrying element will be the fiber itself and, since graphite is stiffer than glass, you'll get a higher modulus (for the same fiber fraction). Off-axis, the load is shared much more with the matrix and the stiffness is a lot lower.

If you have multi-ply laminates with multiple fiber directions the effect isn't so pronounced although, for equal layups and fiber fractions, I'd expect TiGr to be stiffer than GLARE.

Tom.

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