ABOUT ME
Dr. Ori Yeheskel worked for 40 years (1977-2017) as an engineer and scientist for the Israeli Government, where he served in a series of duties. Part of them includes Group leader of powder technology, coordinator of R&D in ceramic materials as well as a supervisor of few R&D projects that run in parallel. He was one of the pioneers to introduce hot isostatic pressing (HIP) to the Israeli industry. He was the Chair of the Israeli Committee for Powder Technology between 1998 and 2005.
Since 1987 he was a visiting scholar and visiting professor in the USA; NIST, Gaithersburg MD (1987); Drexel University, Pa (2009); UC Davis, Ca (2014). In 2017 he gave seminars on 3D printing in Auckland NZ. In addition, he was a visiting scholar at the Weizmann Institute of Science in Israel working on functional ceramics. As of 2018, he is a material consultant mainly on additive manufacturing of metals.
His main expertise is processing-microstructure-properties relationships in metals and ceramic systems.
MAIN INTERESTS
MANUFACTURING READINESS LEVEL-MRL.
During the development stage of new materials, a process of manufacturing readiness is required to ensure product maturity. We perform the process using a combination of the known protocol Manufacturing- Readiness-Level in combination with nondestructive evaluation methods.
ADDITIVE MANUFACTURING OF METALS
We developed powder bed fusion (BPF) using selected materials (AlSi10 Mg, Ti-6Al-4V). We investigate the relationship between processing parameters- microstructure-physical properties. Both mechanical properties and thermal properties are studied.
STRENGTH AND ELASTIC MODULI OF METALS AND CERAMICS
Mechanical strength is studied tension and compression. Elastic moduli are measured using ultrasonic waves and nano-indentation (NI) was also used. Among the materials studied one can find; steels, TiAl, Y2O3, Si3N4, CeO2 ceramics.
QNDE - QUANTITATIVE NON-DESTRUCTIVE EVALUATION
Nondestructive evaluation (NDE) using ultrasound is used in a variety of materials. The method was further developed to quantitative NDE (QNDE) that uses single sound velocity to evaluate the elastic moduli of homogeneous and isotropic solids. Model materials studied include TiAl, Al2O3, Y2O3, and more.
FUNCTIONAL CERAMICS
Functional materials mainly based on rare-earth oxide were developed by the sintering of nanometric powders and characterizing their electromechanical properties. This study was done at the Weizmann Institue of Science.
STRUCTURAL CERAMICS
Structural ceramics were developed using the sintering of nanometric powders or using HIP. Among the materials studied were Si3N4 towards development in engines, Y2O3 ceramics towards an IR dome in missiles and MgO, and MgAl2O4 for optical purposes. CMC based on alumina with SiC was also studied.
POWDER TECHNOLOGY INCLUDING HOT ISOSTATIC PRESSING- HIP
Introducing technology to a country is a challenging topic. R&D HIP systems developed and used for the early development stage of ceramic engines and for IR domes. Other developments were towards advanced materials in the aerospace industry.