Dependency of tensile strength of ductile cast iron on strain rate and temperature

Abstract To obtain dissimilar joint for easily making multi-material structures, the characteristics of friction welded joint between ductile cast iron (FCD400) and 5052 Al alloy (A5052) was investigated. The relatively high tensile strength of joint was obtained when that was made with a friction speed of 27.5 s−1, a friction pressure of 20 MPa, a friction time of 1.5 s, and a forge pressure of 270 MPa, respectively. However, this joint had approximately 77% in the tensile strength of the A5052 base metal and that was fractured at the weld interface. Although the weld interface had no intermetallic compound layer, the fractured surface at the A5052 side had some graphite particles that were supplied from the FCD400 side. To improve the joint strength, the graphite particles were reduced from the weld faying surface at the FCD400 side by decarburization treatment. The joint had approximately 96% in the tensile strength of the A5052 base metal and that was fractured between the A5052 side and the weld interface. The joint with high tensile strength as well as the possibility improving the fractured point of that were obtained when those were made with opportune friction welding condition and no graphite particles at the weld faying surface of the FCD400 side.

Download Full-text

OS8-26 Hydrogen Absorption Properties and its Effects on the Strain-Rate Dependence of Tensile Fracture in Ferritic Ductile Cast Iron(Fatigue and fracture,OS8 Fatigue and fracture mechanics,STRENGTH OF MATERIALS)

The Abstracts of ATEM International Conference on Advanced Technology in Experimental Mechanics Asian Conference on Experimental Mechanics ◽

10.1299/jsmeatem.2015.14.136 ◽

2015 ◽

Vol 2015.14 (0) ◽

pp. 136

Author(s):

Taishi Ogawa ◽

Takashi Matsuo ◽

Masahiro Endo

Keyword(s):

Cast Iron ◽

Fracture Mechanics ◽

Strain Rate ◽

Hydrogen Absorption ◽

Ductile Cast Iron ◽

Rate Dependence ◽

Tensile Fracture ◽

Absorption Properties ◽

Strength Of Materials ◽

Fatigue And Fracture

Download Full-text

Microstructure and Properties of Cast Iron with Semi-Solid Process Using Cooling Plate Technique

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.457.79 ◽

2010 ◽

Vol 457 ◽

pp. 79-83 ◽

Cited By ~ 2

Author(s):

Mitsuharu Takita

Keyword(s):

Tensile Strength ◽

Cast Iron ◽

Gray Iron ◽

Ductile Cast Iron ◽

Advanced Materials ◽

Damping Capacity ◽

Cooling Plate ◽

Plate Technique ◽

Wide Range ◽

Semi Solid

Semi-solid metal processing with the cooling plate technique is one of the key technologies for producing advanced materials. The multitude of cast iron families with their wide range of mechanical properties, and relatively low costs combined with the advantage of semi-solid processing allow production of high quality cast components from cast iron. The effect of semi-solid processing using the cooling plate technique on the microstructure and the properties of cast iron is studied. The investigated material is hypo-eutectic, hyper-eutectic gray iron, compacted graphite and ductile cast iron. The results indicated that the microstructure (primary austenite and graphite) becomes finer and more globular by increasing the fraction of solid. The tensile strength of semi-solid processed cast iron is relatively high compared with ordinary cast iron. The values of both the tensile strength and the elongation depend on the fraction of solid. The total fracture strength is observed to depend on the graphite morphology as well as the matrix contribution that mainly depends on fraction of solid. The wear resistance and damping capacity of cast iron were investigated as a function of the relative amount of primary fraction of solid.

Download Full-text

EFFECT OF HYDROGEN ON UNIAXIAL TENSILE BEHAVIORS OF A DUCTILE CAST IRON

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512003522 ◽

2012 ◽

Vol 06 ◽

pp. 407-412

Author(s):

K. Matsuno ◽

H. Matsunaga ◽

M. Endo ◽

K. Yanase

Keyword(s):

Cast Iron ◽

Strain Rate ◽

Crack Growth ◽

Crack Tip ◽

Thermal Desorption Spectroscopy ◽

Ductile Cast Iron ◽

Uniaxial Tensile ◽

Matrix Interface ◽

Hydrogen Charging ◽

Graphite Matrix

Effect of the hydrogen-charging on the uniaxial tensile behaviors of a ductile cast iron was investigated. It was found that the hydrogen-charging accelerated the process of crack growth from graphite in the uniaxial tensile loading condition. Further, the accelerated crack growth had a marked influence on the reduction of area at the final fracture (RA) of specimens. For instance, for the uncharged specimens, the RA was nearly constant irrespective of the strain rate. In contrast, for the hydrogen-charged specimens, the RA gradually decreased as the strain rate decreased. Thermal desorption spectroscopy and hydrogen microprint technique revealed that, in the hydrogen-charged specimen, most of solute hydrogen was diffusive one, which was mainly segregated at graphite, graphite/matrix interface zone and pearlite. Based on these experimental observations, we consider that the hydrogen-induced degradation behavior was caused mainly by a combination of the following three mechanisms: (i) supplement of hydrogen to the crack tip from graphite and graphite–matrix interface, (ii) hydrogen-enhanced pearlite cracking and, (iii) successive hydrogen-emission from graphite and additional hydrogen-supplement to the crack tip.

Download Full-text

Influence of nickel addition and casting modulus on the properties of hypo-eutectic ductile cast iron

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb181012023c ◽

2019 ◽

Vol 55 (2) ◽

pp. 283-293 ◽

Cited By ~ 1

Author(s):

E. Colin-García ◽

A. Cruz-Ramírez ◽

G. Reyes-Castellanos ◽

J.A. Romero-Serrano ◽

R.G. Sánchez-Alvarado ◽

...

Keyword(s):

Tensile Strength ◽

Cast Iron ◽

Cooling Rate ◽

Ductile Iron ◽

Ductile Cast Iron ◽

Strength Ratio ◽

Cast Irons ◽

Microstructural Changes ◽

Nodule Count ◽

Nickel Addition

The effect of the casting modulus on the distribution and features of graphite in hypo-eutectic ductile iron unalloyed and alloyed with nickel (0.88 wt %) was studied. The cooling rate of the casting plates of 25.4, 12.7 and 8.5 mm in thickness with a casting modulus of 6.87, 4.46 and 3.31 mm, respectively promotes several microstructural changes, such as cementite precipitation and a noticeable nodule count increment. The nickel addition suppressed the cementite formation and improved the nodule count and nodularity for the three casting modulus evaluated. The nickel addition increased the nodule count in 69, 67 and 128 % for the modulus of 3.31, 4.46 and 6.87 mm, respectively, regarding the unalloyed ductile iron. It was found that the biggest casting modulus produced the biggest nodules with the lowest nodule count for both ductile cast irons. Further to the improvements in the graphite features, the nickel addition allowed to keep almost constant the yield and tensile strength ratio for the different casting modulus.

Download Full-text

Research on Tensile Behaviour of New Structural Material MoNiCa

Materials Science ◽

10.5755/j01.ms.25.3.23079 ◽

2019 ◽

Vol 25 (3) ◽

pp. 292-296 ◽

Cited By ~ 3

Author(s):

Aliaksandr BAHDANOVICH ◽

Regita BENDIKIENE ◽

Ramunas CESNAVICIUS ◽

Antanas CIUPLYS ◽

Vytautas GRIGAS ◽

...

Keyword(s):

Tensile Strength ◽

Cast Iron ◽

Structural Material ◽

High Efficiency ◽

Critical Mass ◽

Ductile Cast Iron ◽

Carbon Equivalent ◽

Tensile Behaviour ◽

Strength Increase ◽

Heat Treated

This article presents the results of a set of innovative research to analyse a new structural material – steel like austempered ductile cast iron with mechanical properties similar to heat-treated steel, and with technological and exploitation characteristic close to high-strength cast iron with nodular graphite. Specific examples of its high efficiency for the manufacture of critical, mass and heavy-loaded components of modern machinery and equipment are presented. New structural material MoNiCa was tested on tension and was compared to commercial grades of austempered ductile cast irons and heat treated steels. Unconventional behaviour of examined material was observed: with tensile strength increase to almost 1600 MPa the metal became less brittle. Hardness test revealed another distinctive feature of new material that there is no linear relation between strength and hardness increase, different hardness values ~ 40 HRC or ~ 55 HRC can be achieved with the same tensile strength 1000 – 1200 MPa. Microscopic analysis demonstrated of sophisticated structure formed owing to different regimes of austempering treatment. Specific properties emerged from successful ratio of three elements Mo, Ni, and Cu (carbon equivalent), and properly chosen heat treatment modes. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.23079

Download Full-text