Aluminum castings have limited strength and stiffness and tend to exhibit brittle fracture behavior under fatigue loading. These properties can be significantly improved, however, as this study shows, by reinforcing cast aluminum parts with magnesium metal-matrix composite structures. In order to obtain a bond between the cast Al and fiber-reinforced Mg composite surfaces, Al alloy (Al 99 and AlSi 12 ) layers were deposited on the Mg structures by thermal spraying. The mechanical properties of the bonding were assessed via single-lap shear and adhesive tensile tests along with optical microsection analysis. Hybrid aluminum alloy AlSi 10 Mg castings incorporating coated Mg-MMC inserts were also produced and examined, validating the general approach, while revealing that heat input to the MMC structure must be reduced through design or process adaptations.

Thermal sprayed coatings are already used for the wear protection of cylinder bores since more than five years in the automotive industry, primarily in Europe. The adhesion of the coating on the different possible substrates is a key factor for the success of this operation. This paper gives an overview of the different potential processes used for the surface preparation prior to coating deposition. The influence of different substrate materials will be discussed also. Aluminum casting alloys, magnesium base materials, cast iron and also steel substrates will be considered in this paper. The safety and economical aspects of the different processes are considered also. Further, the paper will give an update of the state of the art of the thermal spraying of cylinder bores and the important aspect regarding the saving of energy resource.

Different thermal spray processes are being used to provide coatings for cylinder bores in automotive engines. The internal plasma spraying technology described in this paper applies protective layers to cylinder surfaces in engine blocks made of AlSi cast alloys. This method enables a significant reduction in the coefficient of friction, a reduction in oil consumption, and an increase in wear resistance compared to cast iron, the standard material for cylinder liners. Paper includes a German-language abstract.

In the automotive industry, efforts to lower the cost of manufacturing and reduce the weight of an automobile are an ongoing process. Plasma spraying of cylinder bores on engine blocks made of light cast alloys has been developed over the five years. This paper provides an overview of the actual situation of the technology for coating cylinder bores, from cast material to non-destructive testing. The aspects of both finishing using honing technology and testing are to be seen as an important part of plasma spray technology for cylinder bores. The paper discusses the results of laboratory and field tests in Europe, Japan, and the United States. This shows that the plasma spraying process is a proven and cost-effective solution for coating cylinder bores. The launch aspect is also discussed. Paper includes a German-language abstract.