T1 Test to check molten metal flow and trial production
Metalmold temperature approximately 95°C
Temperatureduring pouring about 1010°C
Molten metal flow is very good.
Moltenmetal sufficiently fills the mold up to up-hill part for degassing.
Goodrun of molten metal was observed even when the temperatures varied slightly dueto repeated pouring experiment.
Therun of the molten metal was about the same with fast and with slow flow of themolten metal supplied to the product part.
Adefect was found in trial production caused by shrinkage in the part sandwichedby the core, which is the part that solidifies last.
T2 Teeter mold test
Result: good It can be used for Permanent mold casting
Internalshrinkage showed a smooth surface.
Incolor check at the deepest part of the shrinkage, a small amount of roughtexture was observed.It is within the range with no problem.
Thinand deep smooth shrinkage was observed, but we believe the material is suitablefor Permanent mold casting.
Shrinkagetends to be deeper compared to that of common brass, but this can beaccommodated by metal mold plan.
T3 Confirmation of mechanical properties
Tensile strength: 483 N/mm2 Degree of elongation: 45%
Greatly exceeds the standards for common brass and bronze materials.
T4 Analysis and confirmation of molten metal components
| Cu | Sn | Pb | Zn | Ｐ | Si | Cd | ||
|---|---|---|---|---|---|---|---|---|
| 1. | JIS Standard value | 74.0-78.0 | 0.6Max | 0.25Max | 18.5-22.5 | 0.05-0.2 | 2.7-3.4 | |
| 2. | Purchased materials | 76.08 | 0.001 | 0.011 | 20.72 | 0.094 | 3.11 | 3ppm |
| 3. | Before melting | 76.6 | 0.004 | 0.006 | 19.87 | 0.108 | 3.38 | 3ppm |
| 4. | At the time of test production | 76.3 | 0.004 | 0.005 | 20.19 | 0.11 | 3.33 | 3ppm |
Moltenmetal management is relatively easy
T5 Confirming processability
Veryhard and tough compared to common brass.
Chipsare larger.
Can beprocessed if the conditions are changed. (Reduce the number of rotations and increase the feed speed.)
T6 Evaluation of pressure resistance of trial production
Result
Thistrial product was not perfect, but good results were obtained.Effectsof metal mold plan are significant.
Preliminary trial production
Leakagewas observed in part of the trial production.It wassandwiched by core sand and leaked at what seems to be the final solidificationspot. Therewas no leakage at the part in direct contact with the metal mold.
True trial production
It canbe improved through thickness settings and the way molten metal flows based onthe metal mold plan.Afterchanging the plan and thickness setting of the product, the results in truetrial production were good.
Results and evaluation
Metalmold castability is good.As itis also developed as a material for Permanent mold casting, mass production throughlow-pressure Permanent mold casting can be easily accomplished.
However,the features of the plan must be changed from that for commonly used leadedbrass material.
Moltenmetal flow was good, and mechanical properties were better than common brass inPermanent mold casting. Therefore, we can expect a reduced weight metal moldcasting by decreased thickness.