Ortopedia

BÖHLER A220SC is a low carbon, chromium nickel and molybdenum steel. Structure homogeneous, stable austenite. Weldable with analogous filler metal giving fully austenitic deposit. Resistant to intergranular corrosion in the temperature range up to 750°F (400°C). Resistance to acids having a reducing effect, like diluted sulphuric acid and hydrochloric acid is good. The steel is not susceptible to pitting, crevice and stress corrosion cracking in media containing chloride ions and possesses excellent resistance to the attack of urea and biocompatibility. Cold forming properties are good. The steel is capable of taking a mirror finish. The steel is produced as a remelt grade and thus meets the usual requirements for steel purity as specified for implant material.

BÖHLER L035 is a 35-cobalt-35-nickel-20-chromium-10-molybdenum wrought alloy (UNS R30035) used for the production of surgical implants. This alloy composition has been successfully used in human implants. Long-term clinical experience has shown an acceptable biological response. The exceptional properties of BÖHLER L035 result from its chemical composition, high-quality melting technology, cold forming and heat treatment. It is a vacuum induction melted (VIM) and vacuum arc remelted (VAR) superalloy. BÖHLER L035 is a nickel-cobalt based multiphase alloy system with a unique combination of properties e.g. extremely high strength, toughness, ductility and excellent corrosion resistance. The alloy can be strengthened and aged in the factory to achieve strength values of max. 260 to 300 ksi (1793-2086 MPa) and stress corrosion cracking (SCC) resistance even in hydrogen sulphide. The BÖHLER L035 alloy resists pitting and crevice corrosion caused by seawater, chloride solutions and other corrosive environments, e.g. mineral acids (nitric, hydrochloric, sulphuric acid).

BÖHLER P513 è un acciaio inossidabile austenitico saldabile, non magnetico, resistente all’acqua di mare e alla corrosione intercristallina. Offre la migliore resistenza all’abrasione tra tutti gli acciai inossidabili. La resistenza alla corrosione di BÖHLER P513 è superiore a quella degli acciai Cr-Ni austenitici convenzionali (tipo 304) e persino migliore rispetto agli acciai Cr-Ni-Mo (tipo 316) nelle condizioni di prova standard contro la corrosione da vaiolatura da cloruri, la corrosione sotto sforzo e la corrosione crevice. BÖHLER P513 è una lega con un alto contenuto di silicio e manganese, arricchita con azoto, che funziona bene anche ad alte temperature, intorno ai 1800 ºF. Il silicio e il manganese prevengono l’usura e il grippaggio anche nello stato ricotto. Resistenze meccaniche più elevate possono essere ottenute mediante deformazione a freddo, ma ciò non migliora significativamente la resistenza all’abrasione. BÖHLER P513 è utilizzato nei settori aerospaziale, alimentare e farmaceutico, petrolifero, petrolchimico, chirurgico e chimico, ad esempio per steli e sedi di valvole, sistemi di fissaggio, schermature, sistemi di trasmissione a catena, perni, boccole e cuscinetti a rulli, anelli di usura e pistoni nelle pompe.

BÖHLER P558 is a high-nitrogen 11% manganese-17% chromium-3% molybdenum-nickel stainless steel for surgical implants. Its metallurgical requirements include a fine-grained, austenitic microstructure without delta ferrite, low inclusion content, and resistance to intergranular corrosion. BÖHLER P558 also exhibits pitting and crevice corrosion resistance that is significantly better than the reference material in Specification F138 and exceeds the material values ​​specified in Specification F1314 and Specification F1586. Biocompatibility tests for this material have been positive and meet the requirements of the test standards used. The chemical composition of this steel features a high carbon content, along with high nitrogen content. The high carbon content is considered critical in the conventional metallurgy of chromium-nickel stainless steels, but the simultaneous alloying of nitrogen and carbon in BÖHLER P558 has a beneficial effect on the stabilization of the austenitic phase, extends the range of austenite stability to lower solution annealing temperatures, increases corrosion resistance, and leads to better toughness properties.