Projectile impact contact time

AI Thread Summary
Determining contact time during a projectile impact on a plate requires knowledge of material properties, including yield and ultimate strength, as well as geometry and elastic properties of both the projectile and plate. The relationship between force, area, and pressure is central to this analysis, necessitating accurate calculations of contact time. While simple formulas may not suffice due to the complexity of collisions, finite element software can aid in non-destructive scenarios. The discussion highlights three potential impact outcomes: no indentation, indentation, and penetration, which depend on comparing pressure to the plate's material strengths. Understanding these factors is essential for assessing whether the plate can withstand the impact.
AleksanderP90
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I am interested to know if there is possible to find out the contact time by a colliding object into a plate, given material properties? My object is to find out the pressure on a plate using force acting on an area.

What i know:

Mass of both projectile and target plate
Impact velocity of projectile
Density of both projectile and target plate
I also know yield strength, ultimate strength.. for the plate.
 
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If the object is really to know the pressure then I think you will need to know the geometry and elastic properties of the plate and also that of the projectile.
 
Well I know the dimensions of the bullet and plate, like radius, length and width, height of the plate. I could also know some elastic properties of the plate if I find a table that would give me those properties as a material.

The main thing I want to know if there is some way to calculate the contact time. That way I can calculate the Pressure with Force/Area. (I need the time in the force calculations)
 
AleksanderP90 said:
Well I know the dimensions of the bullet and plate, like radius, length and width, height of the plate. I could also know some elastic properties of the plate if I find a table that would give me those properties as a material.

Check out all the complicated stuff that goes on in such collisions:

https://www.youtube.com/watch?v=QfDoQwIAaXg

You can't seriously expect a simple formula for pressure, based on some basic parameters. For non destructive collisions you could use FE-software. But the destructive stuff would be a challenge even with that.
 
I know that this subject is very complicated, and that is why I want to know a way to calculate contact given material properties, that way I can find out if the plate will withstand the pressure from a bullet. There are three different scenarios: No indentation and bullet does not leave a mark, indentation where bullet hits, and last the bullet will penetrate the target.
I have watched that video a lot, and to decide what scenario a bullet will do, I only need to check pressure against the Yield strength and ultimate Strength for the plate. I don't want to simulate the complete process, only first find out what scenario I am dealing with.
 
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