Prevention of Fracture of Cracked Steel Bars Using Laser: Part III—Case of High Carbon Steel

1988 ◽  
Vol 110 (4) ◽  
pp. 319-324
Author(s):  
Akira Kato
Keyword(s):  
Tensile Strength ◽  
Fatigue Strength ◽  
Carbon Steel ◽  
Laser Welding ◽  
Base Metal ◽  
High Carbon Steel ◽  
High Carbon ◽  
Bending Fatigue ◽  
Static Tensile ◽  
Bending Fatigue Strength

The effect of laser welding on prevention of the fracture of cracked shafts of a high carbon steel are presented. Static tensile strength and rotary bending fatigue strength were obtained using shaft specimens of AISI W1 which were welded by a CO2 laser around a precrack. Since the welded region became extremely hard and brittle, both the strengths of laser-welded specimens were lower than those of non-welded specimens. However, the strengths were increased higher than those of non-welded specimens after tempering the specimens. It was found that when tempered at 600°C after laser welding, the rotary bending fatigue strength of specimens with a crack smaller than 12 mm rose similar to that of the base metal, and when tempered at 700° C, the static tensile strength of specimens with a crack smaller than 12mm rose similar to that of the base metal. Therefore, it was shown that the laser welding is very effective to prevent fracture of high carbon steels.

scholarly journals Laser Welding Dissimilar High-Strength Steel Alloys with Complex Geometries

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 792 ◽  
Author(s):  
Panos Efthymiadis ◽  
Khalid Nor
Keyword(s):  
Carbon Steel ◽  
Laser Welding ◽  
Cross Sections ◽  
High Carbon Steel ◽  
High Strength Steels ◽  
High Strength ◽  
Low Carbon ◽  
High Carbon ◽  
Material Chemistry ◽  
Metallurgical Defects

Laser welding of dissimilar high-strength steels was performed in this study for two different geometries, flat and circular samples with material thicknesses of 5 and 8 mm. The material combinations were a low carbon to a medium or high carbon steel. Three different welding systems were employed: a Nd:YAG, a CO2 and a fiber laser. The process stability was evaluated for all the experiments. The resulting full penetration welds were inspected for their surface quality at the top and bottom of the specimens. Cross sections were taken to investigate the resulting microstructures and the metallurgical defects of the welds, such as cracks and pores. Significant hardening occurred in the weld region and the highest hardness values occurred in the Heat Affected Zone (HAZ) of the high carbon steel. The occurrence of weld defects depends strongly on the component geometry. The resulting microstructures within the weld were also predicted using neural network-simulated Continuous Cooling Transformation (CCT) diagrams and predicted the occurrence of a mixture of microstructures, such as bainite, martensite and pearlite, depending on the material chemistry. The thermal fields were measured with thermocouples and revealed the strong influence of component geometry on the cooling rate which in term defines the microstructures forming in the weld and the occurring hardness.

Effect of Adhesive Hardening Treatment on Adhesion Tensile Strength of a High Carbon Steel

1989 ◽  
Vol 75 (5) ◽  
pp. 806-811
Author(s):  
Iwao SAWAI ◽  
Yoshio OKUNO ◽  
Ken SUZUKI ◽  
Toshihei MISAWA
Keyword(s):  
Tensile Strength ◽  
Carbon Steel ◽  
High Carbon Steel ◽  
High Carbon ◽  
Hardening Treatment

The Influence of the Value of Single Draft on Mechanical-Technological Properties of High Carbon Steel Wires

2010 ◽  
Vol 165 ◽  
pp. 371-376 ◽  
Author(s):  
Maciej Suliga
Keyword(s):  
Tensile Strength ◽  
Carbon Steel ◽  
High Carbon Steel ◽  
Wire Drawing ◽  
Strength Properties ◽  
Drawing Process ◽  
Technological Properties ◽  
High Carbon ◽  
Steel Wires ◽  
Optimal Value

In this work the influence of value of single draft on mechanical-technological properties of high carbon steel wires was evaluated. For wires drawn with medium single draft (10.4 %, 15.5 % and 26.5 %) the investigation of mechanical-technological properties was performed thereby providing results on yield strength, tensile strength, elongation, contraction, number of twist and number of band. On the basis of numerical analysis of wire drawing process the influence of the value of single draft on inhomogeneity of strain was determined. It was established that in the range of medium single drafts 10-26 % used in drawing process of high carbon steel wires large single drafts cause the increase of their strength properties by deterioration of their plasticity properties. It was demonstrated that the increase of strength properties in wires drawn with larger single drafts is related to the occurrence of higher non-dilatational strain, which cause additional work hardening of material. The theoretical-experimental analysis of drawing of high carbon steel wires enabled evaluation of optimal value of single drafts by which it can be used relatively the most advantageous useful properties of wires. Obtained research results can be applied while designing the production process of high carbon steel wires.

scholarly journals The Structural and Strength Changes Resulting from Modification of Heat Treatment of High Carbon Steel

2016 ◽  
Vol 61 (2) ◽  
pp. 971-976 ◽  
Author(s):  
D. Grygier ◽  
M. Rutkowska-Gorczyca ◽  
R. Jasiński ◽  
W. Dudziński
Keyword(s):  
Heat Treatment ◽  
Fatigue Strength ◽  
Carbon Steel ◽  
High Carbon Steel ◽  
Cold Drawing ◽  
Pearlitic Steel ◽  
High Carbon ◽  
Plastic Working ◽  
Treatment Results ◽  
Plastic Properties

Abstract Pearlitic steels containing from some 0,8 to 0,95% C belong to the group of unalloyed steels intended for cold drawing or rolling. One of the problems discussed in literature is cracking of pearlitic steel subjected to plastic working, caused by high brittleness of the lamellar precipitations of hard cementite. This issue is extremely important because it affects significantly reduce fatigue strength. The paper presents proposals to modify the process of heat treatment, results in getting a steel with spheroidal structure characterized by better plastic properties, in order to eliminate this problem.

The Influence of the High Speed Multipass Drawing Process on the Fatigue Strength of High Carbon Steel Wires / Wpływ Wielostopniowego Procesu Ciągnienia Z Dużymi Prędkościami Na Wytrzymałość Zmęczeniową Drutów Ze Stali Wysokowęglowej

2012 ◽  
Vol 57 (4) ◽  
pp. 1171-1178
Author(s):  
M. Suliga
Keyword(s):  
Fatigue Strength ◽  
Carbon Steel ◽  
High Speed ◽  
New Technologies ◽  
High Carbon Steel ◽  
Favourable Effect ◽  
Drawing Process ◽  
High Carbon ◽  
Steel Wires ◽  
Drawing Speed

In this work the influence of the drawing speed on fatigue strength of high carbon steel wires has been assessed. The drawing process of φ5.5 mm wires to the final wire of φ1.6 mm was conducted in 11 passes, in industrial conditions, by means of a modern Koch multi-die drawing machine. The drawing speeds in the last passes were: 5, 10, 15 and 20 m/s. For φ1.6 mm wires the investigation of fatigue strength has been carried out. In order to explain the effect of drawing speed on fatigue strength of rope wires, the roughness of drawn wires have been also determined. In addition, the numerical analysis of the drawing process on the base of Drawing 2D in which distribution of redundant strain, has been shown. The data of investigations prove the favourable effect of high drawing speed on fatigue strength of drawn wires. It was found that the better fatigue strength of wires drawn at the speed of 20 m/s compared to the wires drawn at the speeds of 5-15 m/s is associated with a better geometric structure of the surface of those wires. In addition to the high fatigue strength of the wires drawn with high speed is related to theirs higher redundant strain. The obtained data investigation can be applied in wire industry while implementing the new technologies of high speed drawing process of high carbon steel wires.

scholarly journals The Analysis of the Mechanical Properties of High Carbon Steel Wires after Multipass High Speed Drawning Process in Conventional and Hydrodynamic Dies

2014 ◽  
Vol 59 (2) ◽  
pp. 681-685 ◽  
Author(s):  
M. Suliga
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Carbon Steel ◽  
Yield Strength ◽  
High Speed ◽  
High Carbon Steel ◽  
Strength Properties ◽  
High Carbon ◽  
Steel Wires ◽  
Drawing Speed

Abstract In this work the influence of the drawing speed on lubrication conditions and mechanical properties of high carbon steel wires drawn in conventional and hydrodynamic dies has been assessed. The drawing process of ϕ5.5 mm wires to the final wire of ϕ1.7 mm was conducted in 12 passes, in industrial conditions, by means of a modern Koch multi-die drawing machine. The drawing speeds in the last passes were: 5, 10, 15, 20 and 25 m/s. For final wires ϕ1.7 mm the investigation of mechanical properties has been carried out, in which yield strength, tensile strength, uniform and total elongation and also number of twists were determined. It has been shown that the increase of drawing speed from 5 m/s up to 25 m/s caused the increase by 6% strength properties and decrease of plasticity properties by 10%. Higher values of tensile strength and yield strength of the wires drawn conventionally with high speeds are associated with worse conditions, while in case of wires drawn hydrodynamically the main factor which caused the increase of strength properties was high lubricant pressure in hydrodynamic die, which caused the increase of total draft.

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