Review of material testing methods

Ispitivanje materijala izrazito je bitno. Danas je u upotrebi puno različitih materijala i vrlo je važno da zadovoljavaju traženu kvalitetu. Materijali nisu idealni, ali je bitno ako postoje greške da se pronađu, u tu svrhu provode se ispitivanja. Materijali se ispituju razornim (DT) i nerazornim metodama (NDT). Ovaj završni rad opisuje te metode i njihovu upotrebu, prednosti i nedostatke. NDT (Non – destructive testing) metode imaju primjenu u praksi za razne vrste površinskih i podpovršinskih grešaka, i ne oštećuju ispitivani objekt. Nerazorne metode (NDT) nazivaju se i defektoskopija. Ispitivanja se provode: penetrantskom kontrolom (PK), ultrazvučnom kontrolom (UT), magnetskom kontrolom (MT), vizualnom metodom (VT) i radiografskom kontrolom (RT). DT(Destructing testing) metode imaju primjenu za ispitivanje materijala pri različitim opterećenjima. Materijal se ispitivanjem oštećuje pa su potrebni dodatni uzorci materijala. Razorna ispitivanja su najprikladnija i ekonomična za proizvode koji će se masovno proizvoditi, budući da je trošak uništavanja malog broja uzoraka zanemariv. Obično nije ekonomično napraviti razorno ispitivanje kada je potrebno proizvesti samo jedan ili vrlo mali broj proizvoda. Metoda se odabire ovisno o traženim svojstvima ispitivanog materijala. Ispitivanja se provode: statičkim vlačnim pokusom, statičkim tlačnim pokusom, ispitivanjem tvrdoće, ispitivanjem udarnog rada loma i savojnim ispitivanjem. Eksperimentalni dio ovoga rada opisuje utvrđivanje kemijskog sastava materijala kemijskom analizom te ispitivanje tvrdoće Brinell metodom, nakon toga se ispituje zavareni spoj penetrantskom metodom. Eksperimentalni dio obuhvaća pripremu ispitivanja, postupak ispitivanja, detektiranje grešaka, analizu rezultata i zaključak.Material testing is extremely important. It is important that the material is proper and satisfies all expected conditions. Today, a lot of different materials are in use, very important is to satisfies the required quality. Materials are not ideal, but it is important if there are errors, to find them, so testing is done to prevent failures and to improve the quality. Materials are testing by destructive (DT) and non-destructive methods (NDT). This final work describes these methods and their usage, advantages and disadvantages. The methods are chosen according to the type of the object being tested, the failures we are looking for or the equipment we have. Non - destructive testing methods (NDT) are applied in practice for various types of surface and subsurface errors, and do not damage the object. Non-destructive methods (NDT) are also called defectoscopy. The tests are performed by penetrating control (PK), ultrasonic test (UT), magnetic test (MT), visual test (VT) and radiographic test (RT). DT (Destructing Testing) methods have application for testing materials at different loads. The material is damaged by testing, so we need additional sample for test. Destructing tests are most appropriate and cost-effective for mass-produced products, as the cost of destroying a small number of samples is negligible. Usually it is not economical to do a destructing test when it is necessary to produce only one or very few products. The method is selected depending on the required properties of the tested material. The tests are performed by static tensile test, static pressure test, hardness test, impact test, bending test. The experimental part of this work describes the proving of the material by chemical analysis, and hardness testing by the Brinell method, and testing welded joint by penetrant control. The experimental part includes the preparation for the test, the test procedure, the detection of mistakes, analysis and conclusion