We are in the process of preparing powder metallurgy specimens from copper alloy powders (Both brass and bronze). We are searching for a binder material to bind the alloy powders during the sintering process. Kindly suggest some good binding materials with their percentage of addition.
Thank you all in advance.
If you work with aqueous suspensions in powder production, then only water-soluble polymers are applicable as a binder. I like polyvinyl alcohol (PVA) best, which leaves very little residue when sintered in inert gas. PVA is cheap and well distributed. Metilcellulose ( wallpaper paste ) are also suitable for the aqueous route of powder metallurgy. The necessary amount of these binders is 0.1-0.5 wt.% of the amount of metal powder.
Elsewhere at this forum stearic acid was selected as processing control agent (PCA) for the ball milling stage with copper-based powder mixture (not identified), hence prior to sintering: https://www.researchgate.net/post/What_does_1_stearic_acid_as_processing_control_agent_mean_in_Ball_Milling_of_Copper_based_composite
You are not describing which kind of sinter process and which athmosphere you are going to use. In case of reducing atmosphere like H2 or cracked ammonia the amount of residues is not so important because the gas is removing the residues. Stearic acid reduces the pressing forces butis not a strong binder for cold pressing. Also PVA has limitations as a binder. Metylcellulose leaves plenty of residues. Very common nowadays is Polyvenylbutyrol (PVB). PVB is available from Evonik (Degalan). A nice alertnativ is a binder called GB600 available from Dr. Fritsch (www.dr-fritsch.de). All the best for your trials.
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Powders