ELASTOSIL® M 4643 A/B and MinghuiLink RTV-4150 are both high-hardness addition-cure mold silicones, with M 4643 at approximately 48 Shore A and RTV-4150 at 50±2 Shore A. M 4643 emphasizes long working time, accurate reproduction and resistance to casting resins, while RTV-4150 offers simpler 1:1 mixing, lower and more balanced component viscosity and faster published curing.
Addition-Cure Silicone
Platinum-Cure Silicone
ELASTOSIL® M 4643 A/B and RTV-4150 are closely matched high-hardness mold silicones, but they favor different production priorities. M 4643 is better suited to demanding reproduction molds, undercuts and processes that benefit from a 90-minute working window. RTV-4150 is better aligned with users who prioritize simple 1:1 mixing, lower component viscosity and faster published curing.
ELASTOSIL® M 4643 A/B and RTV-4150 are closely matched in hardness, at approximately 48 Shore A and 50±2 Shore A respectively. Both are suited to relatively rigid reusable molds, with processing characteristics and application requirements being the main differences.
M 4643 uses a 9:1 mix ratio and has a 90-minute pot life, while RTV-4150 uses a simpler 1:1 system with approximately 30–40 minutes working time. M 4643 therefore provides more processing time for large or complex molds, while RTV-4150 is easier to proportion and has lower, more balanced component viscosities.
Mechanical performance is mixed. M 4643 publishes approximately 5 MPa tensile strength, >10 N/mm tear strength and 300% elongation, compared with 4.6±0.5 MPa, 28±0.5 N/mm and 350±50% for RTV-4150. M 4643 has the higher published tensile value, while RTV-4150 has higher published tear strength and elongation.
WACKER specifically positions M 4643 for reproduction molds with undercuts and resistance to common casting resins, while RTV-4150 is positioned more broadly for high-hardness reusable molds and routine casting. M 4643 is therefore better aligned with demanding reproduction and longer processing, while RTV-4150 favors simpler handling and faster routine production.
| Technical Parameter | WACKER ELASTOSIL® M 4643 A/B | MinghuiLink RTV-4150 |
|---|---|---|
| Silicone Type | Addition-cure RTV-2 | Platinum-cure silicone |
| Color | Gray | Translucent |
| Mix Ratio | 9:1 by weight | 1:1 by weight or volume |
| Shore Hardness | Approx. 48 Shore A | 50±2 Shore A |
| Viscosity | 40,000 mPa·s (Part A) | 7,000±200 mPa·s (Part A) |
| Working / Pot Life | 90 min | 30–40 min |
| Demold / Cure Time | 12 h tack-free | 5–6 h cure |
| Tensile Strength | Approx. 5 MPa | 4.6±0.5 MPa |
| Tear Strength | >10 N/mm | 28±0.5 N/mm |
| Elongation | 300% | 350±50% |
| Shrinkage | <0.1% | ≤0.1% |
| Temperature Resistance | Not publicly listed as an equivalent numerical service rating | Up to 250°C / 482°F |
| Typical Applications | Reproduction molds, casting-resin molds and undercut models requiring mold rigidity | Reusable molds, rapid prototyping and general high-hardness casting applications |
| Technical Data Sources | ELASTOSIL® M 4643 A/B | RTV-4150 |
| Key Factor | WACKER ELASTOSIL® M 4643 A/B | MinghuiLink RTV-4150 | What It Means |
|---|---|---|---|
| Hardness | Approx. 48 Shore A | 50±2 Shore A | Both target the high-hardness range, with RTV-4150 slightly harder on the published values. |
| Mix Ratio | 9:1 | 1:1 | RTV-4150 is simpler for manual batching. |
| Working Time | 90 min | 35 min | M 4643 provides substantially more processing time for large or complex molds. |
| Component Viscosity | 40,000 / 800 mPa·s | 7,000 / 6,500 mPa·s | RTV-4150 publishes lower and more balanced component viscosities. |
| Tensile Strength | Approx. 5 MPa | 4.6±0.5 MPa | M 4643 publishes the higher tensile-strength value. |
| Tear Strength | >10 N/mm | 28±0.5 N/mm | RTV-4150 publishes the higher numerical tear-strength value. |
| Elongation | 300% | 350±50% | RTV-4150 publishes higher stretch capability. |
| Reproduction Positioning | Accurate reproduction; undercuts requiring mold rigidity | General high-hardness mold making | M 4643 has the more specific reproduction and undercut positioning. |
| Mold Turnaround | 12 h tack-free | 6 h cure | RTV-4150 is better aligned with faster published routine curing. |
| Application | ELASTOSIL® M 4643 A/B | RTV-4150 |
|---|---|---|
| Complex Reproduction | Strong candidate | Strong candidate |
| Undercut Molds | Strong candidate | Suitable |
| Large / Complex Molds | Strong candidate | Suitable |
| Repeated Casting | Strong candidate | Strong candidate |
| Rapid Routine Production | Suitable | Strong candidate |
| Manual Small-Batch Mixing | Suitable with accurate weighing | Strong candidate |
| Casting Resin Applications | Strong candidate | Strong candidate |
| High-Hardness Molds | Strong candidate | Strong candidate |
| 3D-Printed Masters | Suitable with compatibility testing | Suitable with compatibility testing |
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Competitor specifications are based on publicly available manufacturer documentation, with links to the original sources where available. Missing values are shown as “Not publicly listed” and are not estimated or inferred. Specifications may change, so always check the latest manufacturer documentation and conduct application-specific testing before production use. Product names and trademarks belong to their respective owners. This comparison is provided for technical and informational purposes only and is not endorsed by the brands mentioned.