New Addressable Applications for Rheocasting to Escape from an Oversupplied Market

The current market change for aluminium HPDC castings started with “Dieselgate”. First, there was a shift from diesel to gasoline engines. In the second step, hybrid and battery-powered cars gained significant market shares in sales statistics. Therefore, lucrative powertrain components are falling away. As powertrain foundries still want to utilize their machines to capacity, they are pushing into the structural casting market. As a result, there is an oversupply of casting machines here, which massively depresses prices and, thus, margins for tenders.

With rising energy costs, these declining margins were eaten up, putting foundries into crisis. Implementing Rheocasting at the existing die-casting cells is the solution to entering new market shares that are now not accessible in conventional HPDC.

Some of the new applications are electronic housings, parts with high wall thickness, and fatigue-bearing parts. Because of their high wall thickness and low tolerance for porosity, these parts are commonly manufactured in sand or gravity castings.

Rheocasting is the perfect process for high-wall thickness components. Because of the semisolid melt preparation and the lamellar filling behaviour, these components can be manufactured from the same alloy without pores or voids. This flow behaviour of the semisolid slurry also results in a longer flow length. Slower casting speeds and lower pressure settings result in lower clamping forces. This gives an advantage in production costs and targets battery constructions made of castings and sheet metal.

Structural battery housings must be leak-tight, even in a crash event. Having them in one casting instead of an assembly reduces the leakage area and improves crash performance. The telecommunications industry also relies on Rheocasting.

The power electronics in these 5G modules are significantly larger and generate much more waste heat. Until now, many antennas have been actively cooled or milled from a block of aluminium. The milled housings are significantly too expensive to enable series production. Therefore, the goal is to reproduce the passively cooled modules in die casting. Due to the process, the thermal conductivity in conventional HPDC is around 120 to 130 W/m*K. Similarly, no slim cooling fins can be formed.

Only the Rheocasting process makes it possible to cast other alloys with low proportions of alloying elements, such as AlSi2Mn. This allows fins with a wall thickness of down to 0.4 mm and a thermal conductivity of up to 190 W/m*K. Rheocasting enables access to market segments that are otherwise out of reach. These bring an unbeatable cost advantage against the current suppliers: gravity and sand casters. The low cycle time in Rheocasting brings back the high margins needed to sustain the business. Also, these products can be delivered with even better properties on smaller casting machines.

The original presentation was given at the S2P conference. Thank you, Università degli Studi di Brescia and Associazione Italiana di Metallurgia, for organizing the conference. The complete paper is published in Solid State Phenomena, Vol. 348. The paper is available for purchase when you follow the link.

When you want to start with Rheocasting to bring new profitable castings into your foundry, look no further than the Rheocasting Strategy Development package. Casting-Campus GmbH guides you along the business development to get the order. Then, you have an ROI calculation for the investment into the technology instead of the research budget. Schedule a free Consultation call for more information today.