[Javerh]

There are two areas of engineering at play here: The ball contact that falls into the purview of tribology and the ball impact that is dealt with dynamics. I'm going to be using metric formulas here:

When two elastic balls touch, they form a circular contact area that has the radius:
a = ( (3*F*R)/(4*E) )^(1/3), where F is the contact force, R is ball radius and E is the modulus of elasticity.

The two balls move relatively towards each other by a certain distance:
d = ( (9*F^2)/(16*(E^2)*R) )^(1/3)

Now, we can assume that the impact is a short impulse equalling the change in inertia. That gives us the impact force:
F = m*v/t

Unfortunately, the impact time cannot be explicitly solved. However, we can assume that the time is simply the length of the movement of the balls divided by the speed of the first ball (I'm winging this!). Through several iterations we can solve the values for generic steel:
Impact time 0.00005917 s
Relative ball movement 0.132 mm (0.0052")
Impact force 39.626 kN (8924 lbf)
Contact area radius 2.048 mm (0.081")

I don't think there is an easy way to determine the energy losses on the chain of balls.
I'm not entirely convinced by my answer. Perhaps someone with better engineering knowledge can check this out.