T1 Test to check molten metal flow and trial production
Metalmold temperature approximately 95°C
Temperatureduring pouring about 1005°C
Molten metal flow is good
Moltenmetal sufficiently fills the mold up to up-hill part for degassing.
Whenthe product was made with a plan with fast molten metal flow supplied toproduct parts, overall run was sufficient.
Metalmold plan for Permanent mold casting has a marked influence on molten metal flow.Adefect was found in trial production caused by shrinkage in the part sandwichedby the core, which is the part that solidifies last.
We believe the defect can be resolved by using adifferent gate thickness and position.Thevarying components due to Zn depletion in molten metal appeared to causechanges in the flow of molten metal.
T2 Teeter mold test
Result: Good It can be used for Permanent mold casting
Insidethe internal shrinkage showed slightly bumpy shrinkage.
Incolor check at the deepest part of the shrinkage, a small amount of roughtexture was observed.(It is within the range with no problem.)
A planthat considers the possibility of relatively large shrinkage is required.
Moltenmetal temperature may not be suitable. Atemperature range must be used that is suitable for Permanent mold casting.
T3 Confirmation of mechanical properties
Tensilestrength: 373 N/mm2 Degreeof elongation: 23%
Standards of common brass material and bronze were met sufficiently.
T4 Analysis and confirmation of molten metal components
| Cu | Sn+Fe | Pb | Zn | Bi | P | Cd | ||
|---|---|---|---|---|---|---|---|---|
| 1. | Standard value | 60.0-62.0 | 0.7-1.1 | 0.1Max | REM | 1.8-2.3 | 0.1Max | 10ppmMax |
| 2. | Purchased materials | 60.93 | 0.86 | 0.022 | REM | 1.89 | 0.08 | 1ppm |
| 3. | Before melting | 61 | 0.82 | 0.012 | 36.13 | 1.96 | 0.076 | 6ppm |
| 4. | At the time of test production | 62.5 | 0.98 | 0.012 | 34.03 | 1.84 | 0.079 | 6ppm |
The material was not developed as a Permanent mold casting material.
Attentionis required as Zn tends to be depleted and the values of Cu and Sn tend toincrease.
T5 Confirming processability
Itappeared to be viscous.
Chipsare small but larger than those of common brass.
Processabilityis good.
T6 Evaluation of pressure resistance of trial production
Result
Thistrial product was not perfect, but good results were obtained.Metal mold plan and casting condition havelarge effects on pressure resistance.
Preliminary trial production
Leakagewas observed in all products in preliminary trial production.Leakagewas observed at the part sandwiched by core sand that solidifies last.Leakagewas observed in some preliminary trial products where coming into directcontact 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
If the components of molten metal are sufficiently managed, metal mold castability by Permanent mold casting is good.
Thismaterial was not developed as a Permanent mold casting material.
It canbe used for sealed type low-pressure Permanent mold casting.
Utilizationin low-pressure Permanent mold casting may be easier than in gravity metal moldcasting method.
However,optimal balance of molten metal components and Permanent mold casting conditions,such as pouring temperature and metal mold temperature, must be investigated.
Importanceof the Permanent mold casting plan is high, and it is necessary to change thecharacteristics of the plan from that used for common lead-containing brass.