Comparison between LPDC and High Voltage Die Casting HPDC, including porosity, heat treatment, mechanics, cost, and applicable scenarios

Comparison between LPDC and High Voltage Die Casting HPDC, including porosity, heat treatment, mechanics, cost, and applicable scenarios
Many customers are torn between choosing low-pressure casting or high-pressure die casting, as the underlying solidification logic of the two processes is completely different; High die-casting efficiency, but unable to undergo T6 heat treatment, resulting in limited pressure sealing performance; Low pressure can be heat-treated, with stable performance and slower pace. Choosing the wrong process can directly lead to project pitfalls.
1、 Quantitative comparison of core indicators
Pores: HPDC has severe gas entrapment and numerous pores, making it unsuitable for high-temperature heat treatment; LPDC charging is smooth, with controllable gas entrainment and T6 solid solution aging capability.
Mechanical properties: HPDC A380 as cast tensile strength 220-280MPa, not suitable for T6; LPDC A356-T6 tensile strength 260-320MPa, high elongation and good toughness.
Wall thickness: HPDC can achieve a thin wall of 0.8-1.5mm; LPDC stable mass production wall thickness ≥ 2.5mm, too thin can easily cause cold insulation.
Beat: HPDC single-mode 30-90s; LPDC single-mode 180-420s, slow beat.
Cost: Lower unit price for large-scale die-casting of simple appearance parts; Medium batch, pressure bearing, heat-treated parts, low pressure comprehensive yield advantage to balance costs.
Testing: HPDC generally does not support X-ray testing of pressure parts; LPDC can meet X-ray and UT testing requirements, and is suitable for hydraulic and water-cooled shells.
Xinfeng Machinery DFM helped customers lock in the process route in the early stage to avoid discovering the inability to heat treat and pressure leakage after die-casting and mold opening.
2、 Their respective strengths and weaknesses
Advantages of high-pressure die casting: thin wall, complex appearance, ultra-high cycle time, and large quantity of consumer parts; Shortcomings: Roll up air holes, unable to T6, low elongation, high risk of pressure leakage, not suitable for alternating loads.
Advantages of low-pressure casting: smooth filling, sequential solidification, T6 heat treatment, controllable looseness, suitable for X-ray pressure parts, good fatigue performance; Shortcomings: slow pace, high mold cost, weak thin-walled forming ability.
Key points of process transformation: die-casting to low pressure, wall thickness to be increased, gate, exhaust, and filling curves to be completely redesigned, and die-casting drawings cannot be used.
3、 Differences in selection preferences among overseas customers
Southeast Asia: Priority is given to die-casting ordinary shells and non stress parts, pursuing low cost and relying on infiltration for leakage protection.
North American new energy water-cooled shell and valve block, mandatory LPDC+T6, rejecting high-pressure die casting to avoid the risk of heat treatment bubbling.
The mainstream low-pressure pressure components in the European hydraulic industry for medium to large quantities; Large quantities of exterior shells are made by die-casting.
Middle Eastern construction machinery thick walled load-bearing brackets prioritize low pressure and value elongation and impact resistance.
4、 Failure chain caused by incorrect process selection
High pressure die-casting is used for the pressure bearing shell, followed by internal air entrainment and heat treatment for bubbling and scrapping. Without heat treatment, the strength and toughness are insufficient, and there is vibration leakage;
The selection of thin-walled exterior parts is low pressure → cold insulation, difficult filling, slow pace, high unit price, and loss of competitiveness;
The die-casting drawing is directly converted to low pressure → the wall thickness is too thin, the filling end is cold sealed, and the yield continues to be low.
5、 Long tail traffic layout ideas
Comparison between Low Pressure Casting and High Pressure Die Casting, Differences between LPDC and HPDC, Selection of Low Pressure or Die Casting for Water Cooled Shell, aimed at project engineers and procurement.
keywords LPDC vs HPDC aluminum casting、low pressure casting vs high pressure die casting；
Question class: Can HPDC aluminum go through T6 heat treatment;
Comparative category: HPDC A380 vs LPDC A356 T6 mechanical property.
Suitable for process selection and DFM pre evaluation special pages.
6、 Common misconceptions in the industry
Misconception 1: Both die-casting and low-pressure casting are made of aluminum, and the drawings can be used interchangeably. The filling, exhaust, and solidification logic are completely different.
Misconception 2: Die casting has higher strength. Die casting only provides as cast strength and cannot be heat treated, resulting in a much lower elongation than T6 low-pressure parts.
Misconception 3: Low pressure is definitely more expensive than die-casting, and the yield of pressure bearing parts in die-casting is poor, with more infiltration repairs, resulting in higher overall costs.
FAQ
Q: Can T6 heat treatment be performed on high-pressure die-casting?
A: Conventional methods are not feasible. Internal air entrainment and heating can cause bubbles to bulge.
Q: What is the minimum wall thickness for low-pressure stable mass production?
A：≥2.5mm。
Q: What are the commonly used grades of HPDC?
A：A380、ADC12。
Q: LPDC mainstream brand?
A：A356。
Q: Which one is suitable for X-ray pressure shell?
A: LPDC low voltage casting.
Q: Which beat is faster?
A: HPDC high voltage die-casting.
Q: Which elongation rate is better?
A: A356-T6 low-pressure castings.
Q: Is thin-walled appearance preferred?
A: High pressure die-casting.