Essential Procurement Checklist for Low-Pressure Castings Revealed

As the global new energy vehicle (NEV) industry enters the large-scale development phase, demand for core housing components in electric drive systems and power battery packs is growing rapidly. Motor housings and battery pack housingsare critical structural parts of NEV powertrains; their quality directly impacts vehicle safety, reliability, and service life. For procurement professionals in the new energy sector, establishing a systematic procurement checklist for low-Pressure Casting [https://www.htprecisioncast.com/pressure-casting/]s is fundamental to ensuring supply chain quality and cost control.

I. Why Low-Pressure Casting Is the Preferred Process for NEV Housings

In the manufacturing of motor and battery housings, process selection directly determines internal casting quality and service performance. Low-pressure casting (LPC)works by introducing dry compressed air (typically maintained at 20-100 kPa) into a sealed crucible, pushing molten metal upward through a riser tube and gating system to fill the mold cavity smoothly, followed by solidification under pressure. Compared to high-Pressure Die Casting [https://www.htprecisioncast.com/pressure-die-casting/], LPC features extremely stable mold filling with minimal turbulence and drastically reduced gas entrapment, resulting in far lower internal porosity than gravity castings.

NEV motor housings feature complex structures with average wall thicknesses of 4-5 mm, 6-7 mm spiral water-cooling channels in sidewalls, and embedded steel bearing bushings at the base. These complex castings integrating water cooling and structural load-bearing demand exceptional internal density and airtightness. LPC's stable filling and pressure-solidification characteristics effectively eliminate shrinkage cavities and gas porosity, ensuring watertight performance under high pressure. For battery pack housings, large thin-walled structures (3-5 mm) also rely on LPC for complete filling and overall sealing integrity.

II. Core Procurement Elements: Material Specifications

Aluminum alloy selection [https://www.htprecisioncast.com/excellent-application-of-aluminum-alloy-low-pressure-casting-in-the-electromechanical-industry-product/]is the primary technical decision in the procurement checklist. In NEV motor and battery housing applications, A356 (AlSi7Mg) alloy is the most widely used grade. With approximately 7% silicon content, it improves casting fluidity via eutectic phase formation, while magnesium provides precipitation strengthening (forming MgAl phases) to significantly enhance strength.

When defining material specifications, procurement teams must focus on the following alloy composition controls:

* Silicon (Si): Maintain 6-12% for optimal filling and reduced shrinkage; >13% causes network silicon formation and reduced toughness
* Magnesium (Mg): Recommended 0.25-3%; excess increases oxide film formation and porosity risks
* Copper (Cu): Strictly control 0.5-3.2%; excess reduces fluidity and increases hot cracking tendency
* Impurities: Zinc (Zn)



This release was published on openPR.