Electromagnetism: What materials create the best magnet?

My hypothesis is that the steel bolt will be the best of both experiments because steel is just iron and carbon. Iron is a good ferrous metal. That makes a good electromagnet material. I think that the other metals will not work but if they do they will be very weak. I believe the stainless steel may work as it still has iron in it.

The only main research I did in this project was figuring out how to make an electromagnet.

I reduced the amount of variables in my experiments by first making sure that I used exactly 100 loops in each magnet because that would effect the power of the magnet. I also added a buck converter to keep the voltage at exactly 2.7 volts.

In both experiments I had gotten bolts and copper insulated wire and did exactly 100 loops on the bolts and added tape to both ends to hold the wire in place. For my first experiment I built a slide and pulley system out of string and lego with spots for my magnet and paperclip to sit. I then drew paperclips close to the magnet and when they attached to the electromagnet I wrote down the results. This was meant to measure the magnetic field.

For my second experiment I created a tower to hold the magnet so I could slowly attach paperclips until one fell off. This was meant to measure magnetic capacity.

For both experiments I tested each metal 3 times. I then wrote my results on a graph.

An interesting observation I had is that the zinc bolt actually retained some magnetism when turned off.

I have concluded that when making an electromagnet, of the non-iron substitutes, steel is the best material to use. Zinc is second. Zinc also holds a bit of residual magnetism which is interesting. I expected stainless steel to at least slightly work. I did a bit of research and found that zinc is actually non magnetic so i'm thinking my zinc bolt is plated. I wonder if it would work if I had a full zinc bolt.

hilaroad.com/camp/projects/magnet.html