I have started pressure die casting of aluminium just recenly. I am doing it with LK machine 500 ton and casting crank cases of 70cc engines. My products weigh around 2500 grams inclusive of runner maximum and machine is good for even 5kgs shot according to specification. My problem is that sticking of material is too high. On average my product sticks inside mould after every 100 shots. Secondly I am getting porsity or even leakage in my product. Being a part of engine leakage is not acceptable.
How can I overcome these problems?
The problem of castings sticking to die is not uncommon. This mainly occurs due to insufficient cooling of the dies. from your message it is unclear whether you are using any cooling circuits to your die. Die coatings avoids this probleam to a certain extent but not compleate. it is better to use a cooling circuit in your die to carry the heat away if your mold is large enough.
Or you will have to provide sufficient time for your mold to cool down between fixed intervals.
You should ask your die maker if he could make some kind of cooling arrangements for your die. Pls let me know if the probleam is solved.