scholarly journals Influencing Factors and Control Strategies of Heat Treatment Deformation of Metal Materials

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Qiang Li ◽  
Yutao Wang
Keyword(s):  
Heat Treatment ◽  
Influencing Factors ◽  
Thermal Processing ◽  
Control Strategies ◽  
Mechanical Parts ◽  
Performance Requirements ◽  
Heat Treated ◽  
Metal Materials ◽  
And Control

In the thermal processing of metal materials, the performance of thematerial is more stable, and the heat-treated materials are processed into parts to make the performance more excellent and more in line with the performance requirements of mechanical parts. However, in thermal processing, metal materials are prone to problems, such as deformation, deformation of the appearance of metal materials, and fatal effects on the processing of mechanical parts. Therefore, this paper focuses on solving the causes of deformation in the thermal processing of metal materials, as well as solutions to improve the problems in the processing of metal materials.

Subpasteurization Heat Treatment to Inactivate Lipase and Control Bacterial Growth in Raw Milk

1982 ◽  
Vol 45 (6) ◽  
pp. 513-515 ◽  
Author(s):  
G. F. SENYK ◽  
R. R. ZALL ◽  
W. F. SHIPE
Keyword(s):  
Heat Treatment ◽  
Lipase Activity ◽  
Raw Milk ◽  
Heat Treatments ◽  
Plate Count ◽  
Psychrotrophic Bacteria ◽  
Standard Plate Count ◽  
Heat Treated ◽  
Standard Plate ◽  
And Control

Raw milk was heat-treated under subpasteurization and suprapasteurization conditions, cooled and stored for up to 72 h at 4.4 and 6.7°C. Milk lipase activity and bacteria counts were monitored in both unheated and heated milks. Inhibition of milk lipase activity ranged from 42 to 98% for treatments of 57.2°C for 10 sec to 73.9°C for 10 sec, respectively. The logs of Standard Plate Count after 72 h of storage at 6.7°C were 6.56, 4.86, 4.31, 4.00 and 2.82 for unheated and 10-sec heat treatments at 57.2, 65.6, 73.9 and 82.2°C, respectively. Psychrotrophic Bacteria Counts were also lower in the heated milks than in the unheated milk. The logs of Psychrotrophic Bacteria Counts after 72 h of storage at 6.7°C were 6.21, 2.45, 2.27, 1.33 and 1.00 for unheated and 10-sec heat treatments at 57.2, 65.6, 73.9 and 82.2°C, respectively. Heat treatment of raw milk supplies would result in limiting action of the milk lipase system and growth of bacteria.

scholarly journals Heat Treatments Delay and Reduce the Ethylene Climacteric in Carnation Flowers (Dianthus caryophyllus L. cv. `White Sim')

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 460B-460
Author(s):  
Sven Verlinden ◽  
William R. Woodson
Keyword(s):  
Heat Treatment ◽  
Ethylene Production ◽  
Dianthus Caryophyllus ◽  
Acc Oxidase ◽  
Acc Synthase ◽  
Heat Treatments ◽  
Horticultural Crops ◽  
Beneficial Effects ◽  
Heat Treated ◽  
And Control

High-temperature treatments can be used for disinfestation of a variety of horticultural crops. Carnation flowers were subjected to a heat treatment in order to determine if it is a viable option for disinfestation of this crop. Flowers were exposed to 45°C for 24 hr in the dark, while control flowers were held at RT for 24 hr in the dark. Subsequently, the flowers were held at RT in the light and monitored for ethylene production, an indicator of imminent floral senescence. In the heat-treated flowers, the ethylene climacteric occurred at 96 hr after the heat treatment, a delay of 12 hr when compared to the control. Peak ethylene production was decreased by 25% to 30% in heat-treated flowers. Northern blot analysis of the ethylene biosynthetic pathway genes, ACC synthase, and ACC oxidase, showed that the expression of these genes is delayed by 8 to 16 hr in heat-treated flowers. This indicates that the delay and decrease in ethylene production is at least, in part, due to a delay or reduction in the expression of these genes. Further investigation revealed a decreased responsiveness of the petals to ethylene. Petals from heat-treated and control flowers were exposed to 1 ppm ethylene for 0, 0.5, 1, 2, 4, 6, 12, and 32 hr. The heat-treated petals again showed a delay and a decrease in maximum ethylene production after exposure to ethylene. A delay in expression of ACC synthase and ACC oxidase was also observed. The beneficial effects of exposing carnation flowers to high temperatures, a delay in ethylene production, and reduced responsiveness to ethylene, suggest that heat treatments could be used for disinfestation of this crop.

scholarly journals Quality and Cell Wall Components of `Anna' and `Granny Smith' Apples Treated with Heat, Calcium, and Ethylene

1990 ◽  
Vol 115 (6) ◽  
pp. 954-958 ◽  
Author(s):  
Joshua D. Klein ◽  
Susan Lurie ◽  
Ruth Ben-Arie
Keyword(s):  
Heat Treatment ◽  
Cell Wall ◽  
Shelf Life ◽  
Cell Walls ◽  
Cortical Tissue ◽  
Cell Wall Components ◽  
Pectin Content ◽  
Heat Treated ◽  
And Control ◽  
Wall Components

`Anna' and `Granny Smith' apples (Malus domestics Borkh.) that were held at 38C for 4 days before storage at 0C not only were firmer than controls upon removal from storage, but also softened more slowly during shelf life at 17C. Skin yellowing and loss of acidity attendant upon the heat treatment were not prevented by dipping fruit in 2% CaCl2 before heating. Both heat-treated and control fruit softened at the same rate upon exposure to ethylene at 100 μl·liter-1 upon removal from storage. The insoluble pectin content of cortical tissues was higher in heat-treated fruit than in controls after 10 days at 17C, while soluble pectin levels were lower. Arabinose and xylose levels were lower in cell walls from heat-treated cortical tissue, but the treatment had no effect on loss of galactose residues during shelf life.

scholarly journals EFFECTS OF HEAT TREATMENT ON SOME CHEMICAL COMPOUND AND MECHANICAL PROPERTIES OF BLACK PINE WOOD

Wood Research ◽  
2021 ◽  
Vol 66 (4) ◽  
pp. 621-629
Author(s):  
SAHIN AKYUREK ◽  
MURAT AKMAN ◽  
MURAT OZALP
Keyword(s):  
Heat Treatment ◽  
Compression Strength ◽  
Chemical Compound ◽  
Bending Strength ◽  
Lignin Content ◽  
Pinus Nigra ◽  
Black Pine ◽  
Pine Wood ◽  
Heat Treated ◽  
And Control

In this study, effects of heat treatment on bending strength, compression strength, chemical compound and solubility of Black pine wood (Pinus nigra J.F.var. seneriana)was examined.For this purpose, Black pine wood samples were kept in temperature of 250°C for 2 hours. Test results of heat-treated Black pine wood and control samples indicated that mechanical characteristics including compression strength and bending strength were affected negatively with heat treatment. Bending strength of heat treated and non-treated test samples were 129 and 76 N.mm-2, respectively. Compression strength of heat treated and non-treated test samples were 53 and 43N.mm-2, resp.In addition, level of extractives, cellulose and hemicellulose decreased while lignin content increased with percentage of 40%. Significant decreases occurred in all chemical solubility values.

The Effect of Thermal Processing in Vacuum on the Water Adsorption Characteristics of Carbon Black

1992 ◽  
Vol 270 ◽  
Author(s):  
Kurt D. Schachner ◽  
Paul E. Thoma
Keyword(s):  
Heat Treatment ◽  
Relative Humidity ◽  
Carbon Black ◽  
Thermal Processing ◽  
Heat Treatment Temperature ◽  
Water Adsorption ◽  
Treatment Temperature ◽  
Carbon Particles ◽  
Heat Treated ◽  
Oxygen Complexes

ABSTRACTCommercially available carbon black contains oxygen complexes on its surface that affect the surface properties of the carbon. Water adsorption on the surface of carbon black is influenced by the amount and type of oxygen complexes present. When carbon black is heated in vacuum at sufficiently high temperatures, removal of the oxygen complexes occurs and the surface of the carbon particles is modified. The amount of water adsorbed by the carbon is dependent on the vacuum heat treatment temperature. As the heat treatment temperature increases, water adsorption on the carbon decreases.Commercially available electrically conductive carbon black adsorbs from 1.25% to 2.50% water when exposed to 50% relative humidity for 24 hours at 25°C. This variation in water adsorption is due to a difference in the amount of oxygen complexes on the surface of the carbon. The carbon with more oxygen complexes adsorbs more water. However, when this carbon black is heat treated at 1200°C for 4 hours in a vacuum of 1 × 10−5 torr or better, the water adsorbed by the carbon is 0.4% when exposed to 50% relative humidity. Data showing the dependence of water adsorption on vacuum thermal processing are presented and discussed.

Effect of a Complex Heat Treatment on the Structure of 300M Steel

1981 ◽  
Vol 39 ◽  
pp. 312-313
Author(s):  
R. Padmanabhan ◽  
W. E. Wood
Keyword(s):  
Heat Treatment ◽  
Metal Carbides ◽  
Austenite Grain Size ◽  
300M Steel ◽  
Heat Treated ◽  
Strain Fracture ◽  
Prior Austenite Grain Size ◽  
Short Time ◽  
Final Tempering ◽  
Similar Yield

Intermediate high temperature tempering prior to subsequent reaustenitization has been shown to double the plane strain fracture toughness as compared to conventionally heat treated UHSLA steels, at similar yield strength levels. The precipitation (during tempering) of metal carbides and their subsequent partial redissolution and refinement (during reaustenitization), in addition to the reduction in the prior austenite grain size during the cycling operation have all been suggested to contribute to the observed improvement in the mechanical properties. In this investigation, 300M steel was initially austenitized at 1143°K and then subjected to intermediate tempering at 923°K for 1 hr. before reaustenitizing at 1123°K for a short time and final tempering at 583°K. The changes in the microstructure responsible for the improvement in the properties have been studied and compared with conventionally heat treated steel. Fig. 1 shows interlath films of retained austenite produced during conventionally heat treatment.

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