Jerry Thiel

University of Northern Iowa | UNI · Department of Industrial Technology

The design freedom of 3D printing allows for new mold designs—not possible with traditional approaches—such as helical sprues and spatially varying lattice castings. However, research on the curing time of printed molds, including the aging, requires more exploration. This study describes the experiments of 3D printed specimens in which embedded en...

Additive Manufacturing is enabling the casting of complex geometries directly from digital design data, including 3D-scanned and reverse-engineered structures and even functionally graded lattices. By ink jetting binder into a bed of sand layer-by-layer, dimensionally precise sand molds and cores can be printed to serve as soft tooling for sand cas...

3D sand printing is an emerging technology that is enabling new possibilities in metal casting with respect to part complexity, casting design, and rapid mold production. The 3D printing technology, also known as additive manufacturing, is a binder jetting process which involves selectively depositing a furan-based binder into a sand bed one thin l...

For many years, researchers in the foundry industry and universities have been developing testing protocols to evaluate the physical, performance and emission characteristics of prepared green sand during pouring, cooling and shakeout. This paper will review the testing protocol and methods utilized in the collection and evaluation of these charact...

In this work, real-time in-process monitoring of core motion in metal castings is demonstrated though the use of two emerging technologies. 3D sand printing (3DSP) is a binder jetting additive manufacturing process that is quickly manifesting itself as a technological disrupter in the metal casting industry. Based on its direct digital manufacturin...

Additive manufacturing, also commonly referred to as 3D printing, stands to transform sand casting with binder jetting technology that can create sand molds with unmatched geometric complexity. With printed sand molds, castings can be optimized with regard to the strength-versus-weight trade-off and structures such as periodic lattices are now avai...

Surface finish is an integral part of casting quality specifications. Rough internal surface finishes on castings can cause the loss of efficiency for both fluids and high-velocity gasses, and such is the case for turbocharger and intake manifold components. The University of Northern Iowa has been investigating mold material characteristics that a...

Computer-based process modeling has long been used for simulating the casting of metals. The information from these simulations has allowed metalcasters to reduce the occurrence of some defects that result from the metal’s volumetric contraction or entrainment of gasses while filling of the mold cavity. The majority of the analysis of the casting p...

Three-dimensional printing of sand molds and cores is changing the way castings are produced. During the last 5 years major advances in equipment have allowed metalcasters to realize casting designs at faster speeds than ever before. The elimination of tooling for mold and cores assemblies has allowed the industry new flexibility in design optimiza...

Studies were conducted at the University of Northern Iowa Metal Casting Center to determine the mechanisms that cause veining defects in iron and steel castings. Advanced testing methods along with computer casting simulations were used to evaluate various sand mixtures for the propensity to form casting veins. It was found that two forces act on t...

Titanium alloys remain some of the most versatile alloys available with high strength to weight ratios and excellent resistance to corrosion. Its use as an engineering material in cast components has been limited due to its high cost, some of which results from the casting process. Because of the strong reactivity with oxygen, current methods of pr...

Casting defects that are a result of the thermal expansion of silica sand have always posed difficulties for the metal caster. Veining, scabs, rattails and castings out of dimensional tolerances are only a few of the defects that are associated with the detrimental expansion silica sand. The following study was funded by multiple member companies o...