بررسي اثر درجه رقت و لايه واسط بر مقاومت به سايش لايه روكش سخت پايه Fe-Cr-C جوشكاري شده به روش SMAWبر روي فولاد ساده كربني

Investigating the effect of degree of dilution and interlayer on the abrasion resistance of the hard-wired coated layer of Fe-Cr-C based on SMAW method on plane carbon steel

در اﯾﻦ ﺗﺤﻘﯿﻖ ﻫﺪف، ﺑﺮرﺳﯽ اﺛﺮ درﺟﻪ رﻗﺖ و ﻻﯾﻪ واﺳﻂ ﺑﺮ ﻣﻘﺎوﻣﺖ ﺑﻪ ﺳﺎﯾﺶ ﻻﯾﻪ روﮐﺶ ﺳﺨﺖ ﭘﺎﯾﻪ Fe-Cr-C ﺟﻮﺷﮑﺎري ﺷﺪه ﺑﻪ روش SMAW ﺑﺮ روي ﻓﻮﻻد ﺳﺎده ﮐﺮﺑﻨﯽ St37 ﻣﯽ ﺑﺎﺷﺪ، ﺑﻪ ﻫﻤﯿﻦ ﻣﻨﻈﻮر ﺷﺶ ﻗﻄﻌﻪ ﻓﻮﻻد ﺳﺎده ﮐﺮﺑﻨﯽ St37 در اﺑﻌﺎد300×200×10 ﻣﯿﻠﯽ ﻣﺘﺮ ﺑﻪ ﻋﻨﻮان ﻓﻠﺰ ﭘﺎﯾﻪ اﻧﺘﺨﺎب و ﻋﻤﻠﯿﺎت روﮐﺶ ﮐﺎري روي ﺳﻪ ﻧﻤﻮﻧﻪ ﺑﺪون ﻻﯾﻪ واﺳﻂ و روي ﺳﻪ ﻧﻤﻮﻧﻪ ﺑﺎ ﻻﯾﻪ واﺳﻂ اﻧﺠﺎم ﺷﺪ. ﺑﻌﺪ از اﻧﺠﺎم ﻋﻤﻠﯿﺎت ﺟﻮﺷﮑﺎري، آزﻣﻮن ﺳﺨﺘﯽ و ﺳﺎﯾﺶ روي ﻧﻤﻮﻧﻪﻫﺎ اﻧﺠﺎم ﺷﺪ. ﺑﺮرﺳﯽ ﻧﺘﺎﯾﺞ آزﻣﻮن ﺳﺨﺘﯽ ﻧﺸﺎن داد ﮐﻪ ﺑﺎ اﻓﺰاﯾﺶ ﺗﻌﺪاد ﻻﯾﻪ روﮐﺶ ﺳﺨﺖ، ﻣﻘﺪار ﺳﺨﺘﯽ در ﻫﺮ دو ﺳﺮي ﻧﻤﻮﻧﻪ )ﺑﺎ ﻻﯾﻪ واﺳﻂ و ﺑﺪون ﻻﯾﻪ واﺳﻂ( ﻣﻘﺪار ﺳﺨﺘﯽ اﻓﺰاﯾﺶ ﯾﺎﻓﺖ ﺑﻪ ﮔﻮﻧﻪاي ﮐﻪ در ﻧﻤﻮﻧﻪﻫﺎي ﺑﺪون ﻻﯾﻪ واﺳﻂ اﯾﻦ ﻣﻘﺪار از 50 راﮐﻮل ﺑﻪ 56 راﮐﻮل و در ﻧﻤﻮﻧﻪﻫﺎي ﺑﺎ ﻻﯾﻪ واﺳﻂ از 31 راﮐﻮل ﺑﻪ 51 راﮐﻮل رﺳﯿﺪ. ﻫﻤﭽﻨﯿﻦ ﺳﺨﺘﯽ ﻧﻤﻮﻧﻪ ﺑﺎ ﯾﮏ ﻻﯾﻪ روﮐﺶ ﺳﺨﺖ ﺑﺪون ﻻﯾﻪ واﺳﻂ 19 راﮐﻮل از ﺳﺨﺘﯽ ﻧﻤﻮﻧﻪ ﺑﺎ ﯾﮏ ﻻﯾﻪ روﮐﺶ ﺳﺨﺖ ﺑﺎ ﻻﯾﻪ واﺳﻂ ﺑﯿﺸﺘﺮ ﺷﺪ. ﺑﺮرﺳﯽ رﯾﺰﺳﺎﺧﺘﺎري ﻧﺸﺎن داد ﮐﻪ ﺗﻤﺎﻣﯽ ﻧﻤﻮﻧﻪﻫﺎ داراي ﻓﺎزﻫﺎي آﺳﺘﻨﯿﺖ، ﻣﺎرﺗﻨﺰﯾﺖ و ﮐﺎرﺑﯿﺪ ﺑﻮدهاﻧﺪ و ﺗﻨﻬﺎ ﺗﻔﺎوت در ﻣﯿﺰان اﯾﻦ ﻓﺎزﻫﺎ ﻣﯽﺑﺎﺷﺪ. ﻧﺘﺎﯾﺞ آزﻣﻮن ﺳﺎﯾﺶ ﻧﺸﺎن داد ﮐﻪ ﻣﻘﺪار ﻣﻘﺎوﻣﺖ ﺑﻪ ﺳﺎﯾﺶ در ﻫﺮ دو ﺳﺮي ﻧﻤﻮﻧﻪ )ﺑﺎ ﻻﯾﻪ واﺳﻂ و ﺑﺪون ﻻﯾﻪ واﺳﻂ( ﺑﺎ اﻓﺰاﯾﺶ ﺗﻌﺪاد ﻻﯾﻪﻫﺎي روﮐﺶ ﺳﺨﺖ اﻓﺰاﯾﺶ ﯾﺎﻓﺖ ﺑﻪ ﮔﻮﻧﻪاي ﮐﻪ ﻣﻘﺪار ﮐﺎﻫﺶ ﺟﺮم ﺑﺮاي ﻧﻤﻮﻧﻪﻫﺎي ﺑﺪون ﻻﯾﻪ واﺳﻂ از 0/022 ﮔﺮم ﺑﻪ 0/011 ﮔﺮم و ﺑﺮاي ﻧﻤﻮﻧﻪﻫﺎي ﺑﺎ ﻻﯾﻪ واﺳﻂ از 0/032 ﮔﺮم ﺑﻪ 0/019 ﮔﺮم در ﻣﺴﺎﻓﺖ 300 ﻣﺘﺮ رﺳﯿﺪ. ﻫﻤﭽﻨﯿﻦ ﺑﻪ دﻟﯿﻞ اﺳﺘﺤﺎﻟﻪ آﺳﺘﻨﯿﺖ ﺑﻪ ﻣﺎرﺗﻨﺰﯾﺖ در اﺛﺮ ﺗﻐﯿﯿﺮﺷﮑﻞ ﭘﻼﺳﺘﯿﮏ ﻧﺎﺷﯽ از ﺳﺎﯾﺶ، ﺑﺎ اﻓﺰاﯾﺶ ﻣﺴﺎﻓﺖ ﻟﻐﺰش روﻧﺪ اﻓﺰاﯾﺸﯽ ﺟﺮم ﮐﻨﺪه ﺷﺪه از ﺟﺴﻢ ﮐﺎﻫﺶ ﻣﯽ

In this research, the effect of degree of dilution and interlayer layer on the abrasion resistance of the hard-welded Co-layer of Fe-Cr-C based on SMAW method on the St37 steel carbon steel is studied. To this end, the St37 carbon steel element in the dimension of 10 × 300mm x 200mm was chosen as the base metal, and the SMAW welding operation was performed on three pieces with a hard coat electrode and no interlayer layers, and on three other pieces with a hard coated electrode and an interlayer layer. After welding, abrasion and hardness test was carried out on the samples. The results showed that with increasing the number of hard coating layers, the hardness increased in both series of samples (with intermediate layer and no interlayer layer). Microstructural analysis showed that all samples had austenite, martensitic and carbide phases, and the only difference was the amount of these phases. Also, the amount of wear resistance increased in both series of series (with intermediate layer and no interlayer layer) with increasing number of hard coating layers.